U.S. patent application number 14/318544 was filed with the patent office on 2015-03-12 for abrasive article including shaped abrasive particles.
The applicant listed for this patent is Saint-Gobain Ceramics & Plastics, Inc.. Invention is credited to Kristin Breder, Sujatha Iyengar, Adam D. Lior, David Louapre.
Application Number | 20150068130 14/318544 |
Document ID | / |
Family ID | 52142746 |
Filed Date | 2015-03-12 |
United States Patent
Application |
20150068130 |
Kind Code |
A1 |
Louapre; David ; et
al. |
March 12, 2015 |
ABRASIVE ARTICLE INCLUDING SHAPED ABRASIVE PARTICLES
Abstract
A shaped abrasive particle having a major surface-to-side
surface grinding orientation percent difference (MSGPD) of at least
about 40%.
Inventors: |
Louapre; David; (Newton,
MA) ; Breder; Kristin; (Belchertown, MA) ;
Iyengar; Sujatha; (Northborough, MA) ; Lior; Adam
D.; (Brookline, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Saint-Gobain Ceramics & Plastics, Inc. |
Worcester |
MA |
US |
|
|
Family ID: |
52142746 |
Appl. No.: |
14/318544 |
Filed: |
June 27, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61841155 |
Jun 28, 2013 |
|
|
|
Current U.S.
Class: |
51/309 |
Current CPC
Class: |
B24D 18/0063 20130101;
B24D 11/00 20130101; B01J 2/20 20130101; B01J 2/26 20130101; C09K
3/1409 20130101 |
Class at
Publication: |
51/309 |
International
Class: |
C09K 3/14 20060101
C09K003/14; B24D 11/00 20060101 B24D011/00 |
Claims
1. A shaped abrasive particle comprising a major surface-to-side
surface grinding orientation percent difference (MSGPD) of at least
about 40%.
2. The shaped abrasive particle of claim 1, wherein the shaped
abrasive particle comprises a maximum quartile-to-median percent
difference (MQMPD) of at least about 48%.
3. The shaped abrasive particle of claim 2, wherein the MQMPD is
not greater than about 99%.
4. The shaped abrasive particle of claim 1, wherein the MSGPD is
not greater than about 99%.
5. The shaped abrasive particle of claim 1, wherein the shaped
abrasive particle further comprises a first grinding efficiency
characteristic selected from the group consisting of: a major
surface grinding efficiency upper quartile value (MSUQ) not greater
than about 8.3 kN/mm.sup.2; a major surface grinding efficiency
lower quartile value (MSLQ) not greater than about 8 kN/mm.sup.2; a
side surface grinding efficiency upper quartile value (SSUQ) at
least about 4.5 kN/mm.sup.2; a side surface grinding efficiency
median value (SSM) at least about 3 kN/mm.sup.2; a side surface
grinding efficiency lower quartile value (SSLQ) at least about 2.5
kN/mm.sup.2; a maximum quartile difference (MQD) at least about 6
kN/mm.sup.2; a major surface-to-side surface quartile percent
overlap (MSQPO) of not greater than about 11%, a major surface
grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD) of at least about 1.9
kN/mm.sup.2; a major surface-to-side surface upper quartile percent
difference (MSUQPD) of at least about 54%; a major surface-to-side
surface lower quartile percent difference (MSLQPD) of at least
about 28%; a major surface grinding efficiency time variance (MSTV)
is not greater than about 2 kN/mm.sup.2; and a combination
thereof.
6. The shaped abrasive particle of claim 1, wherein the shaped
abrasive particle comprises a body having a length (l), a width
(w), and a height (h), wherein the width>length, the
length>height, and the width>height.
7. The shaped abrasive particle of claim 1, wherein the shaped
abrasive particle comprises a body having a first major surface, a
second major surface, and at least one side surface extending
between the first major surface and the second major surface.
8. The shaped abrasive particle of claim 7, wherein the body
comprises a major surface corner radius of curvature between about
100 microns and about 800 microns.
9. The shaped abrasive particle of claim 7, wherein the body
comprises a side surface corner radius of curvature between about 1
micron and about 800 microns.
10. The shaped abrasive particle of claim 7, wherein the body
comprises a ratio (SSCR/MSCR) of a side surface corner radius of
curvature (SSCR) to a major surface corner radius of curvature
(MSCR) between about 0.001 and about 1.
11. The shaped abrasive particle of claim 7, wherein the body
comprises a major surface corner radius of curvature greater than a
side surface corner radius of curvature.
12. The shaped abrasive particle of claim 6, wherein the body
comprises a percent flashing of between about 1% and about 20%.
13. The shaped abrasive particle of claim 6, wherein the body
comprises a two-dimensional polygonal shape as viewed in a plane
defined by a length and a width of the body, wherein the body
comprises a shape selected from the group consisting of triangular,
quadrilateral, rectangular, trapezoidal, pentagonal, hexagonal,
heptagonal, octagonal, and a combination thereof.
14. The shaped abrasive particle of claim 1, wherein the shaped
abrasive particle is part of a fixed abrasive article.
15. A batch of abrasive particles comprising a first portion
including a plurality of shaped abrasive particles having a major
surface-to-side surface grinding orientation percent difference
(MSGPD) of at least about 40%.
16. The batch of abrasive particles of claim 15, wherein the batch
of abrasive particles are part of a fixed abrasive article.
17. The batch of abrasive particles of claim 15, wherein the
plurality of shaped abrasive particles of the first portion further
comprise a first grinding efficiency characteristic selected from
the group consisting of: a major surface grinding efficiency upper
quartile value (MSUQ) not greater than about 8.3 kN/mm.sup.2; a
major surface grinding efficiency lower quartile value (MSLQ) not
greater than about 8 kN/mm.sup.2; a side surface grinding
efficiency upper quartile value (SSUQ) at least about 4.5
kN/mm.sup.2; a side surface grinding efficiency median value (SSM)
at least about 3 kN/mm.sup.2; a side surface grinding efficiency
lower quartile value (SSLQ) at least about 2.5 kN/mm.sup.2; a
maximum quartile difference (MQD) at least about 6 kN/mm.sup.2; a
major surface-to-side surface quartile percent overlap (MSQPO) of
not greater than about 11%, a major surface grinding efficiency
median value and side surface grinding efficiency median value
difference (MSMD) of at least about 1.9 kN/mm.sup.2; a major
surface-to-side surface upper quartile percent difference (MSUQPD)
of at least about 54%; a major surface-to-side surface lower
quartile percent difference (MSLQPD) of at least about 28%; a major
surface grinding efficiency time variance (MSTV) is not greater
than about 2 kN/mm.sup.2; and a combination thereof.
18. An abrasive article comprising: a backing: a batch of abrasive
particles comprising a first portion including a plurality of
shaped abrasive particles overlying the backing, wherein the
plurality of shaped abrasive particles of the first portion
comprise at least one first grinding efficiency characteristic of:
a major surface-to-side surface grinding orientation percent
difference (MSGPD) of at least about 40%; a maximum
quartile-to-median percent difference (MQMPD) of at least about
48%; a major surface grinding efficiency median value (MSM) of not
greater than about 4 kN/mm.sup.2; and a combination thereof.
19. The abrasive article of claim 18, wherein a majority of the
plurality of shaped abrasive particles of the first portion of the
batch are arranged in a side orientation relative to the
backing.
20. The abrasive article of claim 18, wherein the batch further
comprises a second portion of shaped abrasive particles, wherein
the second portion of shaped abrasive particles have a second
grinding efficiency characteristic different than the first
grinding efficiency characteristic of the first portion, wherein
the second grinding efficiency characteristic is selected from the
group consisting of: a major surface grinding efficiency upper
quartile value (MSUQ); a major surface grinding efficiency median
value (MSM); a major surface grinding efficiency lower quartile
value (MSLQ); a side surface grinding efficiency upper quartile
value (SSUQ); a side surface grinding efficiency median value
(SSM); a side surface grinding efficiency lower quartile value
(SSLQ); a major surface-to-side surface grinding orientation
percent difference (MSGPD); a maximum quartile-to-median percent
difference (MQMPD); a maximum quartile difference (MQD); a major
surface-to-side surface quartile percent overlap (MSQPO); a major
surface grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD); a major surface-to-side
surface upper quartile percent difference (MSUQPD); a major
surface-to-side surface lower quartile percent difference (MSLQPD);
wherein the major surface grinding efficiency time variance (MSTV);
and a combination thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 U.S.C.
.sctn.119(e) to U.S. Patent Application No. 61/841,155 entitled
"Abrasive Articles Including Shaped Abrasive Particles" by David
Louapre et al., filed Jun. 28, 2013, which is assigned to the
current assignee hereof and incorporated herein by reference in its
entirety.
BACKGROUND
[0002] 1. Field of the Disclosure
[0003] The following is directed to abrasive articles, and
particularly, abrasive articles including shaped abrasive
particles.
[0004] 2. Description of the Related Art
[0005] Abrasive particles and abrasive articles made from abrasive
particles are useful for various material removal operations
including grinding, finishing, and polishing. Depending upon the
type of abrasive material, such abrasive particles can be useful in
shaping or grinding a wide variety of materials and surfaces in the
manufacturing of goods. Certain types of abrasive particles have
been formulated to date that have particular geometries, such as
triangular shaped abrasive particles and abrasive articles
incorporating such objects. See, for example, U.S. Pat. Nos.
5,201,916; 5,366,523; and 5,984,988.
[0006] Three basic technologies that have been employed to produce
abrasive particles having a specified shape are (1) fusion, (2)
sintering, and (3) chemical ceramic. In the fusion process,
abrasive particles can be shaped by a chill roll, the face of which
may or may not be engraved, a mold into which molten material is
poured, or a heat sink material immersed in an aluminum oxide melt.
See, for example, U.S. Pat. No. 3,377,660 (disclosing a process
including flowing molten abrasive material from a furnace onto a
cool rotating casting cylinder, rapidly solidifying the material to
form a thin semisolid curved sheet, densifying the semisolid
material with a pressure roll, and then partially fracturing the
strip of semisolid material by reversing its curvature by pulling
it away from the cylinder with a rapidly driven cooled
conveyor).
[0007] In the sintering process, abrasive particles can be formed
from refractory powders having a particle size of up to 10
micrometers in diameter. Binders can be added to the powders along
with a lubricant and a suitable solvent, e.g., water. The resulting
mixture, mixtures, or slurries can be shaped into platelets or rods
of various lengths and diameters. See, for example, U.S. Pat. No.
3,079,242 (disclosing a method of making abrasive particles from
calcined bauxite material including (1) reducing the material to a
fine powder, (2) compacting under affirmative pressure and forming
the fine particles of said powder into grain sized agglomerations,
and (3) sintering the agglomerations of particles at a temperature
below the fusion temperature of the bauxite to induce limited
recrystallization of the particles, whereby abrasive grains are
produced directly to size).
[0008] Chemical ceramic technology involves converting a colloidal
dispersion or hydrosol (sometimes called a sol), optionally in a
mixture, with solutions of other metal oxide precursors, into a gel
or any other physical state that restrains the mobility of the
components, drying, and firing to obtain a ceramic material. See,
for example, U.S. Pat. Nos. 4,744,802 and 4,848,041.
[0009] Still, there remains a need in the industry for improving
performance, life, and efficacy of abrasive particles, and the
abrasive articles that employ abrasive particles.
SUMMARY
[0010] In one aspect, a shaped abrasive particle comprises a major
surface-to-side surface grinding orientation percent difference
(MSGPD) of at least about 40%.
[0011] In another aspect, a shaped abrasive particle comprises a
maximum quartile-to-median percent difference (MQMPD) of at least
about 48%.
[0012] In yet another aspect, a batch of abrasive particles
comprises a first portion including a plurality of shaped abrasive
particles having a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%.
[0013] For another aspect, a batch of abrasive particles comprises
a first portion including a plurality of shaped abrasive particles
having a maximum quartile-to-median percent difference (MQMPD) of
at least about 48%.
[0014] In still another aspect, a shaped abrasive particle
comprises a major surface grinding efficiency median value (MSM) of
not greater than about 4 kN/mm2.
[0015] According to yet another aspect, an abrasive article
comprises a backing, a batch of abrasive particles comprising a
first portion including a plurality of shaped abrasive particles
overlying the backing. Wherein the plurality of shaped abrasive
particles of the first portion include at least one first grinding
efficiency characteristic of a major surface-to-side surface
grinding orientation percent difference (MSGPD) of at least about
40%, a maximum quartile-to-median percent difference (MQMPD) of at
least about 48%, a major surface grinding efficiency median value
(MSM) of not greater than about 4 kN/mm.sup.2, and a combination
thereof.
[0016] In still one aspect, a method includes removing material
from a workpiece by moving an abrasive article relative to a
surface of the workpiece, the abrasive article includes a backing
and a batch of abrasive particles comprising a first portion
including a plurality of shaped abrasive particles overlying the
backing, wherein the plurality of shaped abrasive particles of the
first portion comprise at least one first grinding efficiency
characteristic of a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%, a
maximum quartile-to-median percent difference (MQMPD) of at least
about 48%, a major surface grinding efficiency median value (MSM)
of not greater than about 4 kN/mm.sup.2, and a combination
thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present disclosure may be better understood, and its
numerous features and advantages made apparent to those skilled in
the art by referencing the accompanying drawings.
[0018] FIG. 1A includes a portion of a system for forming a
particulate material in accordance with an embodiment.
[0019] FIG. 1B includes a portion of the system of FIG. 1A for
forming a particulate material in accordance with an
embodiment.
[0020] FIG. 2 includes a portion of a system for forming a
particulate material in accordance with an embodiment.
[0021] FIG. 3A includes a perspective view illustration of a shaped
abrasive particle according to an embodiment
[0022] FIG. 3B includes a cross-sectional illustration of the
shaped abrasive particle of FIG. 3A.
[0023] FIG. 4 includes a side view of a shaped abrasive particle
and percentage flashing according to an embodiment.
[0024] FIG. 5 includes a cross-sectional illustration of a portion
of a coated abrasive article according to an embodiment.
[0025] FIG. 6 includes a cross-sectional illustration of a portion
of a coated abrasive article according to an embodiment.
[0026] FIG. 7A includes an illustration of a top-view of a major
surface of a shaped abrasive particle according to an
embodiment.
[0027] FIG. 7B includes an illustration of a side-view of a side
surface of a shaped abrasive particle according to an
embodiment.
[0028] FIG. 8 includes a generalized plot of force per total area
removed from the workpiece, which is representative of data derived
from the SGGT.
[0029] FIG. 9 includes a perspective view illustration of a portion
of an abrasive article including shaped abrasive particles having
predetermined orientation characteristics relative to a grinding
direction in accordance with an embodiment.
[0030] FIG. 10 includes an image of two representative shaped
abrasive particles from Sample 51.
[0031] FIG. 11 includes an image of two representative shaped
abrasive particles from Sample CS2
[0032] FIG. 12 includes an image of two representative shaped
abrasive particles from Sample S3.
[0033] FIG. 13 includes an image of two representative shaped
abrasive particles from Sample S4.
[0034] FIG. 14 includes an image of two representative shaped
abrasive particles from Sample CS1.
[0035] FIG. 15 includes a plot of major surface grinding efficiency
and side surface grinding efficiency according to the SGGT for a
conventional sample of shaped abrasive particles and shaped
abrasive particles representative of the embodiments herein.
[0036] FIG. 16 includes images representative of portions of a
coated abrasive according to an embodiment and used to analyze the
orientation of shaped abrasive particles on the backing.
[0037] FIG. 17 includes a plot includes a plot of major surface
grinding efficiency over time according to the SGGT for a shaped
abrasive particles representative of an embodiments herein.
DETAILED DESCRIPTION
[0038] The following is directed to abrasive articles including,
for example, fixed abrasive articles such as coated abrasive
articles. The abrasive articles can include shaped abrasive
particles. Various other uses may be derived for the shaped
abrasive particles. Certain aspects of the embodiments herein are
directed to grinding characteristics of the coated abrasive
articles, and such characteristics are not to be interpreted as
limiting the intended purpose or potential applications of the
coated abrasive articles. Rather, the one or more grinding
characteristics are quantifiable features of the coated abrasive
articles according to known test conditions to demonstrate the
advantages of the coated abrasive articles of the embodiments over
conventional articles.
[0039] Shaped Abrasive Particles
[0040] Various methods may be utilized to obtain shaped abrasive
particles. The particles may be obtained from a commercial source
or fabricated. Various suitable processes may be used to fabricate
the shaped abrasive particles including, but not limited to,
screen-printing, molding, pressing, casting, sectioning, cutting,
dicing, punching, drying, curing, depositing, coating, extruding,
rolling, and a combination thereof.
[0041] FIG. 1A includes an illustration of a system 150 for forming
a shaped abrasive particle in accordance with one, non-limiting
embodiment. The process of forming shaped abrasive particles can be
initiated by forming a mixture 101 including a ceramic material and
a liquid. In particular, the mixture 101 can be a gel formed of a
ceramic powder material and a liquid, wherein the gel can be
characterized as a shape-stable material having the ability to
substantially hold a given shape even in the green (i.e., unfired)
state. In accordance with an embodiment, the gel can be formed of
the ceramic powder material as an integrated network of discrete
particles.
[0042] The mixture 101 may contain a certain content of solid
material, liquid material, and additives such that it has suitable
rheological characteristics for use with the process detailed
herein. That is, in certain instances, the mixture can have a
certain viscosity, and more particularly, suitable rheological
characteristics that form a dimensionally stable phase of material
that can be formed through the process as noted herein. A
dimensionally stable phase of material is a material that can be
formed to have a particular shape and substantially maintain the
shape for at least a portion of the processing subsequent to
forming. In certain instances, the shape may be retained throughout
subsequent processing, such that the shape initially provided in
the forming process is present in the finally-formed object.
[0043] The mixture 101 can be formed to have a particular content
of solid material, such as the ceramic powder material. For
example, in one embodiment, the mixture 101 can have a solids
content of at least about 25 wt %, such as at least about 35 wt %,
or even at least about 38 wt % for the total weight of the mixture
101. Still, in at least one non-limiting embodiment, the solids
content of the mixture 101 can be not greater than about 75 wt %,
such as not greater than about 70 wt %, not greater than about 65
wt %, not greater than about 55 wt %, not greater than about 45 wt
%, or not greater than about 42 wt %. It will be appreciated that
the content of the solids materials in the mixture 101 can be
within a range between any of the minimum and maximum percentages
noted above.
[0044] According to one embodiment, the ceramic powder material can
include an oxide, a nitride, a carbide, a boride, an oxycarbide, an
oxynitride, and a combination thereof. In particular instances, the
ceramic material can include alumina. More specifically, the
ceramic material may include a boehmite material, which may be a
precursor of alpha alumina. The term "boehmite" is generally used
herein to denote alumina hydrates including mineral boehmite,
typically being Al.sub.2O.sub.3.H.sub.2O and having a water content
on the order of 15%, as well as pseudoboehmite, having a water
content higher than 15%, such as 20-38% by weight. It is noted that
boehmite (including pseudoboehmite) has a particular and
identifiable crystal structure, and therefore a unique X-ray
diffraction pattern. As such, boehmite is distinguished from other
aluminous materials including other hydrated aluminas such as ATH
(aluminum trihydroxide), a common precursor material used herein
for the fabrication of boehmite particulate materials.
[0045] Furthermore, the mixture 101 can be formed to have a
particular content of liquid material. Some suitable liquids may
include water. In accordance with one embodiment, the mixture 101
can be formed to have a liquid content less than the solids content
of the mixture 101. In more particular instances, the mixture 101
can have a liquid content of at least about 25 wt % for the total
weight of the mixture 101. In other instances, the amount of liquid
within the mixture 101 can be greater, such as at least about 35 wt
%, at least about 45 wt %, at least about 50 wt %, or even at least
about 58 wt %. Still, in at least one non-limiting embodiment, the
liquid content of the mixture can be not greater than about 75 wt
%, such as not greater than about 70 wt %, not greater than about
65 wt %, not greater than about 62 wt %, or even not greater than
about 60 wt %. It will be appreciated that the content of the
liquid in the mixture 101 can be within a range between any of the
minimum and maximum percentages noted above.
[0046] Furthermore, to facilitate processing and forming shaped
abrasive particles according to embodiments herein, the mixture 101
can have a particular storage modulus. For example, the mixture 101
can have a storage modulus of at least about 1.times.10.sup.4 Pa,
such as at least about 4.times.10.sup.4 Pa, or even at least about
5.times.10.sup.4 Pa. However, in at least one non-limiting
embodiment, the mixture 101 may have a storage modulus of not
greater than about 1.times.10' Pa, such as not greater than about
2.times.10.sup.6 Pa. It will be appreciated that the storage
modulus of the mixture 101 can be within a range between any of the
minimum and maximum values noted above.
[0047] The storage modulus can be measured via a parallel plate
system using ARES or AR-G2 rotational rheometers, with Peltier
plate temperature control systems. For testing, the mixture 101 can
be extruded within a gap between two plates that are set to be
approximately 8 mm apart from each other. After extruding the gel
into the gap, the distance between the two plates defining the gap
is reduced to 2 mm until the mixture 101 completely fills the gap
between the plates. After wiping away excess mixture, the gap is
decreased by 0.1 mm and the test is initiated. The test is an
oscillation strain sweep test conducted with instrument settings of
a strain range between 0.01% to 100%, at 6.28 rad/s (1 Hz), using
25-mm parallel plate and recording 10 points per decade. Within 1
hour after the test completes, the gap is lowered again by 0.1 mm
and the test is repeated. The test can be repeated at least 6
times. The first test may differ from the second and third tests.
Only the results from the second and third tests for each specimen
should be reported.
[0048] Furthermore, to facilitate processing and forming shaped
abrasive particles according to embodiments herein, the mixture 101
can have a particular viscosity. For example, the mixture 101 can
have a viscosity of at least about 4.times.10.sup.3 Pa s, at least
about 5.times.10.sup.3 Pa s, at least about 6.times.10.sup.3 Pa s,
at least about 8.times.10.sup.3 Pa s, at least about
10.times.10.sup.3 Pa s, at least about 20.times.10.sup.3 Pa s, at
least about 30.times.10.sup.3 Pa s, at least about
40.times.10.sup.3 Pa s, at least about 50.times.10.sup.3 Pa s, at
least about 60.times.10.sup.3 Pa s, or at least about
65.times.10.sup.3 Pa s. In at least one non-limiting embodiment,
the mixture 101 may have a viscosity of not greater than about
100.times.10.sup.3 Pa s, such as not greater than about
95.times.10.sup.3 Pa s, not greater than about 90.times.10.sup.3 Pa
s, or even not greater than about 85.times.10.sup.3 Pa s. It will
be appreciated that the viscosity of the mixture 101 can be within
a range between any of the minimum and maximum values noted above.
The viscosity can be measured in the same manner as the storage
modulus as described above.
[0049] Moreover, the mixture 101 can be formed to have a particular
content of organic materials including, for example, organic
additives that can be distinct from the liquid to facilitate
processing and formation of shaped abrasive particles according to
the embodiments herein. Some suitable organic additives can include
stabilizers, binders such as fructose, sucrose, lactose, glucose,
UV curable resins, and the like.
[0050] Notably, the embodiments herein may utilize a mixture 101
that can be distinct from slurries used in conventional forming
operations. For example, the content of organic materials within
the mixture 101 and, in particular, any of the organic additives
noted above, may be a minor amount as compared to other components
within the mixture 101. In at least one embodiment, the mixture 101
can be formed to have not greater than about 30 wt % organic
material for the total weight of the mixture 101. In other
instances, the amount of organic materials may be less, such as not
greater than about 15 wt %, not greater than about 10 wt %, or even
not greater than about 5 wt %. Still, in at least one non-limiting
embodiment, the amount of organic materials within the mixture 101
can be at least about 0.01 wt %, such as at least about 0.5 wt %
for the total weight of the mixture 101. It will be appreciated
that the amount of organic materials in the mixture 101 can be
within a range between any of the minimum and maximum values noted
above.
[0051] Moreover, the mixture 101 can be formed to have a particular
content of acid or base, distinct from the liquid content, to
facilitate processing and formation of shaped abrasive particles
according to the embodiments herein. Some suitable acids or bases
can include nitric acid, sulfuric acid, citric acid, chloric acid,
tartaric acid, phosphoric acid, ammonium nitrate, and ammonium
citrate. According to one particular embodiment in which a nitric
acid additive is used, the mixture 101 can have a pH of less than
about 5, and more particularly, can have a pH within a range
between about 2 and about 4.
[0052] The system 150 of FIG. 1A, can include a die 103. As
illustrated, the mixture 101 can be provided within the interior of
the die 103 and configured to be extruded through a die opening 105
positioned at one end of the die 103. As further illustrated,
extruding can include applying a force 180 (such as a pressure) on
the mixture 101 to facilitate extruding the mixture 101 through the
die opening 105. In an embodiment, the system 150 can generally be
referred to as a screen printing process. During extrusion within
an application zone 183, a screen 151 can be in direct contact with
a portion of a belt 109. The screen printing process can include
extruding the mixture 101 from the die 103 through the die opening
105 in a direction 191. In particular, the screen printing process
may utilize the screen 151 such that, upon extruding the mixture
101 through the die opening 105, the mixture 101 can be forced into
an opening 152 in the screen 151.
[0053] In accordance with an embodiment, a particular pressure may
be utilized during extrusion. For example, the pressure can be at
least about 10 kPa, such as at least about 500 kPa. Still, in at
least one non-limiting embodiment, the pressure utilized during
extrusion can be not greater than about 4 MPa. It will be
appreciated that the pressure used to extrude the mixture 101 can
be within a range between any of the minimum and maximum values
noted above. In particular instances, the consistency of the
pressure delivered by a piston 199 may facilitate improved
processing and formation of shaped abrasive particles. Notably,
controlled delivery of consistent pressure across the mixture 101
and across the width of the die 103 can facilitate improved
processing control and improved dimensional characteristics of the
shaped abrasive particles.
[0054] Referring briefly to FIG. 1B, a portion of the screen 151 is
illustrated. As shown, the screen 151 can include the opening 152,
and more particularly, a plurality of openings 152 extending
through the volume of the screen 151. In accordance with an
embodiment, the openings 152 can have a two-dimensional shape as
viewed in a plane defined by the length (l) and width (w) of the
screen. The two-dimensional shape can include various shapes such
as, for example, polygons, ellipsoids, numerals, Greek alphabet
letters, Latin alphabet letters, Russian alphabet characters,
complex shapes including a combination of polygonal shapes, and a
combination thereof. In particular instances, the openings 152 may
have two-dimensional polygonal shapes such as a triangle, a
rectangle, a quadrilateral, a pentagon, a hexagon, a heptagon, an
octagon, a nonagon, a decagon, and a combination thereof.
[0055] As further illustrated, the screen 151 can have openings 152
that are oriented in a particular manner relative to each other. As
illustrated and in accordance with one embodiment, each of the
openings 152 can have substantially the same orientation relative
to each other, and substantially the same orientation relative to
the surface of the screen. For example, each of the openings 152
can have a first edge 154 defining a first plane 155 for a first
row 156 of the openings 152 extending laterally across a lateral
axis 158 of the screen 151. The first plane 155 can extend in a
direction substantially orthogonal to a longitudinal axis 157 of
the screen 151. However, it will be appreciated, that in other
instances, the openings 152 need not necessarily have the same
orientation relative to each other.
[0056] Moreover, the first row 156 of openings 152 can be oriented
relative to a direction of translation to facilitate particular
processing and controlled formation of shaped abrasive particles.
For example, the openings 152 can be arranged on the screen 151
such that the first plane 155 of the first row 156 defines an angle
relative to the direction of translation 171. As illustrated, the
first plane 155 can define an angle that is substantially
orthogonal to the direction of translation 171. Still, it will be
appreciated that in one embodiment, the openings 152 can be
arranged on the screen 151 such that the first plane 155 of the
first row 156 defines a different angle with respect to the
direction of translation, including for example, an acute angle or
an obtuse angle. Still, it will be appreciated that the openings
152 may not necessarily be arranged in rows. The openings 152 may
be arranged in various particular ordered distributions with
respect to each other on the screen 151, such as in the form of a
two-dimensional pattern. Alternatively, the openings may be
disposed in a random manner on the screen 151.
[0057] Referring again to FIG. 1A, after forcing the mixture 101
through the die opening 105 and a portion of the mixture 101
through the openings 152 in the screen 151, one or more precursor
shaped abrasive particles 123 may be printed on the belt 109
disposed under the screen 151. According to a particular
embodiment, the precursor shaped abrasive particles 123 can have a
shape substantially replicating the shape of the openings 152.
Notably, the mixture 101 can be forced through the screen in rapid
fashion, such that the average residence time of the mixture 101
within the openings 152 can be less than about 2 minutes, less than
about 1 minute, less than about 40 seconds, or even less than about
20 seconds. In particular non-limiting embodiments, the mixture 101
may be substantially unaltered during printing as it travels
through the screen openings 152, thus experiencing no change in the
amount of components from the original mixture, and may experience
no appreciable drying in the openings 152 of the screen 151.
[0058] Additionally, the system 151 can include a bottom stage 198
within the application zone 183. During the process of forming
shaped abrasive particles, the belt 109 can travel over the bottom
stage 198, which can offer a suitable substrate for forming.
According to one embodiment, the bottom stage 198 can include a
particularly rigid construction including, for example, an
inorganic material such as a metal or metal alloy having a
construction suited to facilitating the formation of shaped
abrasive particles according to embodiments herein. Moreover, the
bottom stage 198 can have an upper surface that is in direct
contact with the belt 109 and that has a particular geometry and/or
dimension (e.g., flatness, surface roughness, etc.), which can also
facilitate improved control of dimensional characteristics of the
shaped abrasive particles.
[0059] During operation of the system 150, the screen 151 can be
translated in a direction 153 while the belt 109 can be translated
in a direction 110 substantially similar to the direction 153, at
least within the application zone 183, to facilitate a continuous
printing operation. As such, the precursor shaped abrasive
particles 123 may be printed onto the belt 109 and translated along
the belt 109 to undergo further processing. It will be appreciated
that such further processing can include processes described in the
embodiments herein, including for example, shaping, application of
other materials (e.g., dopant material), drying, and the like.
[0060] In some embodiments, the belt 109 and/or the screen 151 can
be translated while extruding the mixture 101 through the die
opening 105. As illustrated in the system 100, the mixture 101 may
be extruded in a direction 191. The direction of translation 110 of
the belt 109 and/or the screen 151 can be angled relative to the
direction of extrusion 191 of the mixture 101. While the angle
between the direction of translation 110 and the direction of
extrusion 191 is illustrated as substantially orthogonal in the
system 100, other angles are contemplated, including for example,
an acute angle or an obtuse angle.
[0061] The belt 109 and/or the screen 151 may be translated at a
particular rate to facilitate processing. For example, the belt 109
and/or the screen 151 may be translated at a rate of at least about
3 cm/s. In other embodiments, the rate of translation of the belt
109 and/or the screen 151 may be greater, such as at least about 4
cm/s, at least about 6 cm/s, at least about 8 cm/s, or even at
least about 10 cm/s. Still, in at least one non-limiting
embodiment, the belt 109 and/or the screen 151 may be translated in
a direction 110 at a rate of not greater than about 5 m/s, not
greater than about 1 m/s, or even not greater than about 0.5 m/s.
It will be appreciated that the belt 109 and/or the screen 151 may
be translated at a rate within a range between any of the minimum
and maximum values noted above, and moreover, may be translated at
substantially the same rate relative to each other. Furthermore,
for certain processes according to embodiments herein, the rate of
translation of the belt 109 as compared to the rate of extrusion of
the mixture 101 in the direction 191 may be controlled to
facilitate proper processing.
[0062] After the mixture 101 is extruded through the die opening
105, the mixture 101 may be translated along the belt 109 under a
knife edge 107 attached to a surface of the die 103. The knife edge
107 may define a region at the front of the die 103 that
facilitates displacement of the mixture 101 into the openings 152
of the screen 151.
[0063] Certain processing parameters may be controlled to
facilitate formation of particular features of the precursor shaped
abrasive particles 123 and the finally-formed shaped abrasive
particles described herein. Some exemplary process parameters that
can be controlled include a release distance 197, a viscosity of
the mixture, a storage modulus of the mixture, mechanical
properties of the bottom stage, geometric or dimensional
characteristics of the bottom stage, thickness of the screen,
rigidity of the screen, a solid content of the mixture, a carrier
content of the mixture, a release angle, a translation speed, a
temperature, a content of release agent, a pressure exerted on the
mixture, a speed of the belt, and a combination thereof.
[0064] According to one embodiment, one particular process
parameter can include controlling the release distance 197 between
a filling position and a release position. In particular, the
release distance 197 can be a distance measured in a direction 110
of the translation of the belt 109 between the end of the die 103
and the initial point of separation between the screen 151 and the
belt 109. According to one embodiment, controlling the release
distance 197 can affect at least one dimensional characteristic of
the precursor shaped abrasive particles 123 or the finally-formed
shaped abrasive particles. Moreover, control of the release
distance 197 can affect a combination of dimensional
characteristics of the shaped abrasive particles, including but not
limited to, length, width, interior height (hi), variation of
interior height (Vhi), difference in height, profile ratio,
flashing index, dishing index, rake angle, any of the dimensional
characteristic variations of the embodiments herein, and a
combination thereof.
[0065] According to one embodiment, the release distance 197 can be
not greater than a length of the screen 151. In other instances,
the release distance 197 can be not greater than a width of the
screen 151. Still, in one particular embodiment, the release
distance 197 can be not greater than 10 times a largest dimension
of the opening 152 in the screen 151. For example, the openings 152
can have a triangular shape, such as illustrated in FIG. 1B, and
the release distance 197 can be not greater than 10 times the
length of one side of the opening 152 defining the triangular
shape. In other instances, the release distance 197 can be less,
such as not greater than about 8 times the largest dimension of the
opening 152 in the screen 151, such as not greater than about 5
times, not greater than about 3 times, not greater than about 2
times, or even not greater than the largest dimension of the
opening 152 in the screen 151.
[0066] In more particular instances, the release distance 197 can
be not greater than about 30 mm, such as not greater than about 20
mm, or even not greater than about 10 mm. For at least one
embodiment, the release distance can be substantially zero, and
more particularly, can be essentially zero. Accordingly, the
mixture 101 can be disposed into the openings 152 within the
application zone 183 and the screen 151 and the belt 109 may be
separating from each other at the end of the die 103 or even before
the end of the die 103.
[0067] According to one particular method of forming, the release
distance 197 can be essentially zero, which may facilitate
substantially simultaneous filling of the openings 152 with the
mixture 101 and separation between the belt 109 and the screen 151.
For example, before the screen 151 and the belt 109 pass the end of
the die 103 and exit the application zone 183, separation of the
screen 151 and the belt 109 may be initiated. In more particular
embodiments, separation between the screen 151 and the belt 109 may
be initiated immediately after the openings 152 are filled with the
mixture 101, prior to leaving the application zone 183 and while
the screen 151 is located under the die 103. In still another
embodiment, separation between the screen 151 and the belt 109 may
be initiated while the mixture 101 is being placed within the
opening 152 of the screen 151. In an alternative embodiment,
separation between the screen 151 and the belt 109 can be initiated
before the mixture 101 is placed in the openings 152 of the screen
151. For example, before the openings 152 pass under the die
opening 105, the belt 109 and screen 151 are being separated, such
that a gap exists between belt 109 and the screen 151 while the
mixture 101 is being forced into the openings 152.
[0068] For example, FIG. 2 illustrates a printing operation where
the release distance 197 is substantially zero and separation
between the belt 109 and the screen 151 is initiated before the
belt 109 and screen 151 pass under the die opening 105. More
particularly, the release between the belt 109 and the screen 151
is initiated as the belt 109 and screen 151 enter the application
zone 183 and pass under the front of the die 103. Still, it will be
appreciated that in some embodiments, separation of the belt 109
and screen 151 can occur before the belt 109 and screen 151 enter
the application zone 183 (defined by the front of the die 103),
such that the release distance 197 may be a negative value.
[0069] Control of the release distance 197 can facilitate
controlled formation of shaped abrasive particles having improved
dimensional characteristics and improved dimensional tolerances
(e.g., low dimensional characteristic variability). For example,
decreasing the release distance 197 in combination with controlling
other processing parameters can facilitate improved formation of
shaped abrasive particles having greater interior height (hi)
values.
[0070] Additionally, as illustrated in FIG. 2, control of the
separation height 196 between a surface of the belt 109 and a lower
surface 198 of the screen 151 may facilitate controlled formation
of shaped abrasive particles having improved dimensional
characteristics and improved dimensional tolerances (e.g., low
dimensional characteristic variability). The separation height 196
may be related to the thickness of the screen 151, the distance
between the belt 109 and the die 103, and a combination thereof.
Moreover, one or more dimensional characteristics (e.g., interior
height) of the precursor shaped abrasive particles 123 may be
controlled by controlling the separation height 196 and the
thickness of the screen 151. In particular instances, the screen
151 can have an average thickness of not greater than about 700
microns, such as not greater than about 690 microns, not greater
than about 680 microns, not greater than about 670 microns, not
greater than about 650 microns, or not greater than about 640
microns. Still, the average thickness of the screen can be at least
about 100 microns, such as at least about 300 microns, or even at
least about 400 microns.
[0071] In one embodiment the process of controlling can include a
multi-step process that can include measuring, calculating,
adjusting, and a combination thereof. Such processes can be applied
to the process parameter, a dimensional characteristic, a
combination of dimensional characteristics, and a combination
thereof. For example, in one embodiment, controlling can include
measuring one or more dimensional characteristics, calculating one
or more values based on the process of measuring the one or more
dimensional characteristics, and adjusting one or more process
parameters (e.g., the release distance 197) based on the one or
more calculated values. The process of controlling, and
particularly any of the processes of measuring, calculating, and
adjusting may be completed before, after, or during the formation
of the shaped abrasive particles. In one particular embodiment, the
controlling process can be a continuous process, wherein one or
more dimensional characteristics are measured and one or more
process parameters are changed (i.e., adjusted) in response to the
measured dimensional characteristics. For example, the process of
controlling can include measuring a dimensional characteristic such
as a difference in height of the precursor shaped abrasive
particles 123, calculating a difference in height value of the
precursor shaped abrasive particles 123, and changing the release
distance 197 to change the difference in height value of the
precursor shaped abrasive particles 123.
[0072] Referring again to FIG. 1, after extruding the mixture 101
into the openings 152 of the screen 151, the belt 109 and the
screen 151 may be translated to a release zone 185 where the belt
109 and the screen 151 can be separated to facilitate the formation
of the precursor shaped abrasive particles 123. In accordance with
an embodiment, the screen 151 and the belt 109 may be separated
from each other within the release zone 185 at a particular release
angle.
[0073] In fact, as illustrated, the precursor shaped abrasive
particles 123 may be translated through a series of zones wherein
various treating processes may be conducted. Some suitable
exemplary treating processes can include drying, heating, curing,
reacting, radiating, mixing, stirring, agitating, planarizing,
calcining, sintering, comminuting, sieving, doping, and a
combination thereof. According to one embodiment, the precursor
shaped abrasive particles 123 may be translated through an optional
shaping zone 113, wherein at least one exterior surface of the
particles may be shaped as described in embodiments herein.
Furthermore, the precursor shaped abrasive particles 123 may be
translated through an optional application zone 131, wherein a
dopant material can be applied to at least one exterior surface of
the particles as described in embodiments herein. And further, the
precursor shaped abrasive particles 123 may be translated on the
belt 109 through an optional post-forming zone 125, wherein a
variety of processes, including for example, drying, may be
conducted on the precursor shaped abrasive particles 123 as
described in embodiments herein.
[0074] The application zone 131 may be used for applying a material
to at least one exterior surface of one or more precursor shaped
abrasive particles 123. In accordance with an embodiment, a dopant
material may be applied to the precursor shaped abrasive particles
123. More particularly, as illustrated in FIG. 1, the application
zone 131 can be positioned before the post-forming zone 125. As
such, the process of applying a dopant material may be completed on
the precursor shaped abrasive particles 123. However, it will be
appreciated that the application zone 131 may be positioned in
other places within the system 100. For example, the process of
applying a dopant material can be completed after forming the
precursor shaped abrasive particles 123, and more particularly,
after the post-forming zone 125. In yet other instances, which will
be described in more detail herein, the process of applying a
dopant material may be conducted simultaneously with a process of
forming the precursor shaped abrasive particles 123.
[0075] Within the application zone 131, a dopant material may be
applied utilizing various methods including for example, spraying,
dipping, depositing, impregnating, transferring, punching, cutting,
pressing, crushing, and any combination thereof. In particular
instances, the application zone 131 may utilize a spray nozzle, or
a combination of spray nozzles 132 and 133 to spray dopant material
onto the precursor shaped abrasive particles 123.
[0076] In accordance with an embodiment, applying a dopant material
can include the application of a particular material, such as a
precursor. In certain instances, the precursor can be a salt, such
as a metal salt, that includes a dopant material to be incorporated
into the finally-formed shaped abrasive particles. For example, the
metal salt can include an element or compound that is the precursor
to the dopant material. It will be appreciated that the salt
material may be in liquid form, such as in a dispersion comprising
the salt and liquid carrier. The salt may include nitrogen, and
more particularly, can include a nitrate. In other embodiments, the
salt can be a chloride, sulfate, phosphate, and a combination
thereof. In one embodiment, the salt can include a metal nitrate,
and more particularly, consist essentially of a metal nitrate.
[0077] In one embodiment, the dopant material can include an
element or compound such as an alkali element, alkaline earth
element, rare earth element, hafnium, zirconium, niobium, tantalum,
molybdenum, vanadium, or a combination thereof. In one particular
embodiment, the dopant material includes an element or compound
including an element such as lithium, sodium, potassium, magnesium,
calcium, strontium, barium, scandium, yttrium, lanthanum, cesium,
praseodymium, niobium, hafnium, zirconium, tantalum, molybdenum,
vanadium, chromium, cobalt, iron, germanium, manganese, nickel,
titanium, zinc, and a combination thereof.
[0078] In particular instances, the process of applying a dopant
material can include selective placement of the dopant material on
at least one exterior surface of a precursor shaped abrasive
particle 123. For example, the process of applying a dopant
material can include the application of a dopant material to an
upper surface or a bottom surface of the precursor shaped abrasive
particles 123. In still another embodiment, one or more side
surfaces of the precursor shaped abrasive particles 123 can be
treated such that a dopant material is applied thereto. It will be
appreciated that various methods may be used to apply the dopant
material to various exterior surfaces of the precursor shaped
abrasive particles 123. For example, a spraying process may be used
to apply a dopant material to an upper surface or side surface of
the precursor shaped abrasive particles 123. Still, in an
alternative embodiment, a dopant material may be applied to the
bottom surface of the precursor shaped abrasive particles 123
through a process such as dipping, depositing, impregnating, or a
combination thereof. It will be appreciated that a surface of the
belt 109 may be treated with dopant material to facilitate a
transfer of the dopant material to a bottom surface of precursor
shaped abrasive particles 123.
[0079] After forming precursor shaped abrasive particles 123, the
particles may be translated through a post-forming zone 125.
Various processes may be conducted in the post-forming zone 125,
including treatment of the precursor shaped abrasive particles 123.
In one embodiment, the post-forming zone 125 can include a heating
process where the precursor shaped abrasive particles 123 may be
dried. Drying may include removal of a particular content of
material, including volatiles, such as water. In accordance with an
embodiment, the drying process can be conducted at a drying
temperature of not greater than about 300.degree. C., such as not
greater than about 280.degree. C., or even not greater than about
250.degree. C. Still, in one non-limiting embodiment, the drying
process may be conducted at a drying temperature of at least about
50.degree. C. It will be appreciated that the drying temperature
may be within a range between any of the minimum and maximum
temperatures noted above. Furthermore, the precursor shaped
abrasive particles 123 may be translated through the post-forming
zone 125 at a particular rate, such as at least about 0.2 feet/min
and not greater than about 8 feet/min.
[0080] Furthermore, the drying process may be conducted for a
particular duration. For example, the drying process may be not
greater than about six hours.
[0081] After the precursor shaped abrasive particles 123 are
translated through the post-forming zone 125, the precursor shaped
abrasive particles 123 may be removed from the belt 109. The
precursor shaped abrasive particles 123 may be collected in a bin
127 for further processing.
[0082] In accordance with an embodiment, the process of forming
shaped abrasive particles may further comprise a sintering process.
For certain processes of embodiments herein, sintering can be
conducted after collecting the precursor shaped abrasive particles
123 from the belt 109. Alternatively, the sintering may be a
process that is conducted while the precursor shaped abrasive
particles 123 are on the belt 109. Sintering of the precursor
shaped abrasive particles 123 may be utilized to densify the
particles, which are generally in a green state. In a particular
instance, the sintering process can facilitate the formation of a
high-temperature phase of the ceramic material. For example, in one
embodiment, the precursor shaped abrasive particles 123 may be
sintered such that a high-temperature phase of alumina, such as
alpha alumina, is formed. In one instance, a shaped abrasive
particle can comprise at least about 90 wt % alpha alumina for the
total weight of the particle. In other instances, the content of
alpha alumina may be greater such that the shaped abrasive particle
may consist essentially of alpha alumina.
[0083] Additionally, the body of the finally-formed shaped abrasive
particles can have particular two-dimensional shapes. For example,
the body can have a two-dimensional shape, as viewed in a plane
defined by the length and width of the body, and can have a shape
including a polygonal shape, ellipsoidal shape, a numeral, a Greek
alphabet character, a Latin alphabet character, a Russian alphabet
character, a complex shape utilizing a combination of polygonal
shapes and a combination thereof. Particular polygonal shapes
include triangular, rectangular, trapezoidal, pentagonal,
hexagonal, heptagonal, octagonal, nonagonal, decagonal, and any
combination thereof. In another embodiment, the body can include a
two-dimensional shape, as viewed in a plane defined by a length and
a width of the body, including shapes selected from the group
consisting of ellipsoids, Greek alphabet characters, Latin alphabet
characters, Russian alphabet characters, and a combination
thereof.
[0084] FIG. 3A includes a perspective view illustration of a shaped
abrasive particle 300 in accordance with an embodiment.
Additionally, FIG. 3B includes a cross-sectional illustration of
the abrasive particle of FIG. 3A. A body 301 of the shaped abrasive
particle 300 includes an upper major surface 303 (i.e., a first
major surface) and a bottom major surface 304 (i.e., a second major
surface) opposite the upper major surface 303. The upper surface
303 and the bottom surface 304 can be separated from each other by
side surfaces 305, 306, and 307. As illustrated, the body 301 of
the shaped abrasive particle 300 can have a generally triangular
shape as viewed in a plane of the upper surface 303. In particular,
the body 301 can have a length (Lmiddle) as shown in FIG. 3B, which
may be measured at the bottom surface 304 of the body 301 as
extending from a corner 313 through a midpoint 381 of the body 301
to a midpoint at the opposite edge 314 of the body. Alternatively,
the body 301 can be defined by a second length or profile length
(Lp), which is the measure of the dimension of the body 301 from a
side view at the upper surface 303 from a first corner 313 to an
adjacent corner 312. Notably, the dimension of Lmiddle can be a
length defining a distance between a height at a corner (hc) and a
height at a midpoint edge (hm) opposite the corner. The dimension
Lp can be a profile length along a side of the particle 300 (as
seen from a side view such as shown in FIGS. 2A and 2B) defining
the distance between h1 and h2. Reference herein to the length can
refer to either Lmiddle or Lp.
[0085] The body 301 can further include a width (w) that is the
longest dimension of the body 301 and extending along a side. The
body 301 can further include a height (h), which may be a dimension
of the body 301 extending in a direction perpendicular to the
length and width in a direction defined by a side surface of the
body 301. Notably, as will be described in more detail herein, the
body 301 can be defined by various heights depending upon the
location on the body 301. In specific instances, the width can be
greater than or equal to the length, the length can be greater than
or equal to the height, and the width can be greater than or equal
to the height.
[0086] Moreover, reference herein to any dimensional characteristic
(e.g., h1, h2, hi, w, Lmiddle, Lp, and the like) can be reference
to a dimension of a single shaped abrasive particle of a batch, a
median value, or an average value derived from analysis of a
suitable sampling of shaped abrasive particles from a batch. Unless
stated explicitly, reference herein to a dimensional characteristic
can be considered reference to a median value that is a based on a
statistically significant value derived from a sample size of a
suitable number of particles from a batch of particles. Notably,
for certain embodiments herein, the sample size can include at
least 10 randomly selected particles from a batch of particles. A
batch of particles may be a group of particles that are collected
from a single process run. Additionally or alternatively, a batch
of particles may include an amount of shaped abrasive particles
suitable for forming a commercial grade abrasive product, such as
at least about 20 lbs. of particles.
[0087] In accordance with an embodiment, the body 301 of the shaped
abrasive particle can have a first corner height (hc) at a first
region of the body defined by a corner 313. Notably, the corner 313
may represent the point of greatest height on the body 301,
however, the height at the corner 313 does not necessarily
represent the point of greatest height on the body 301. The corner
313 can be defined as a point or region on the body 301 defined by
the joining of the upper surface 303, and two side surfaces 305 and
307. The body 301 may further include other corners, spaced apart
from each other, including for example, corner 311 and corner 312.
As further illustrated, the body 301 can include edges 314, 315,
and 316 that can be separated from each other by the corners 311,
312, and 313. The edge 314 can be defined by an intersection of the
upper surface 303 with the side surface 306. The edge 315 can be
defined by an intersection of the upper surface 303 and side
surface 305 between corners 311 and 313. The edge 316 can be
defined by an intersection of the upper surface 303 and side
surface 307 between corners 312 and 313.
[0088] As further illustrated, the body 301 can include a second
midpoint height (hm) at a second end of the body 301, which can be
defined by a region at the midpoint of the edge 314, which can be
opposite the first end defined by the corner 313. The axis 350 can
extend between the two ends of the body 301. FIG. 3B is a
cross-sectional illustration of the body 301 along the axis 350,
which can extend through a midpoint 381 of the body 301 along the
dimension of length (Lmiddle) between the corner 313 and the
midpoint of the edge 314.
[0089] In accordance with an embodiment, the shaped abrasive
particles of the embodiments herein, including for example, the
particle of FIGS. 3A and 3B can have an average difference in
height, which is a measure of the difference between hc and hm. For
convention herein, average difference in height will be generally
identified as hc-hm, however it is defined as an absolute value of
the difference. Therefore, it will be appreciated that average
difference in height may be calculated as hm-hc when the height of
the body 301 at the midpoint of the edge 314 is greater than the
height at the corner 313. More particularly, the average difference
in height can be calculated based upon a plurality of shaped
abrasive particles from a suitable sample size. The heights hc and
hm of the particles can be measured using a STIL (Sciences et
Techniques Industrielles de la Lumiere--France) Micro Measure 3D
Surface Profilometer (white light (LED) chromatic aberration
technique) and the average difference in height can be calculated
based on the average values of hc and hm from the sample.
[0090] As illustrated in FIG. 3B, in one particular embodiment, the
body 301 of the shaped abrasive particle 300 may have an average
difference in height at different locations at the body 301. The
body 301 can have an average difference in height, which can be the
absolute value of [hc-hm] between the first corner height (hc) and
the second midpoint height (hm) that is at least about 20 microns.
It will be appreciated that average difference in height may be
calculated as hm-hc when the height of the body 301 at a midpoint
of the edge is greater than the height at an opposite corner. In
other instances, the average difference in height [hc-hm] can be at
least about 25 microns, at least about 30 microns, at least about
36 microns, at least about 40 microns, at least about 60 microns,
such as at least about 65 microns, at least about 70 microns, at
least about 75 microns, at least about 80 microns, at least about
90 microns, or even at least about 100 microns. In one non-limiting
embodiment, the average difference in height can be not greater
than about 300 microns, such as not greater than about 250 microns,
not greater than about 220 microns, or even not greater than about
180 microns. It will be appreciated that the average difference in
height can be within a range between any of the minimum and maximum
values noted above. Moreover, it will be appreciated that the
average difference in height can be based upon an average value of
hc. For example, the average height of the body 301 at the corners
(Ahc) can be calculated by measuring the height of the body 301 at
all corners and averaging the values, and may be distinct from a
single value of height at one corner (hc). Accordingly, the average
difference in height may be given by the absolute value of the
equation [Ahc-hi]. Furthermore, it will be appreciated that the
average difference in height can be calculated using a median
interior height (Mhi) calculated from a suitable sample size from a
batch of shaped abrasive particles and an average height at the
corners for all particles in the sample size. Accordingly, the
average difference in height may be given by the absolute value of
the equation [Ahc-Mhi].
[0091] In particular instances, the body 301 can be formed to have
a primary aspect ratio, which is a ratio expressed as width:length,
having a value of at least 1:1. In other instances, the body 301
can be formed such that the primary aspect ratio (w:l) is at least
about 1.5:1, such as at least about 2:1, at least about 4:1, or
even at least about 5:1. Still, in other instances, the abrasive
particle 300 can be formed such that the body 301 has a primary
aspect ratio that is not greater than about 10:1, such as not
greater than 9:1, not greater than about 8:1, or even not greater
than about 5:1. It will be appreciated that the body 301 can have a
primary aspect ratio within a range between any of the ratios noted
above. Furthermore, it will be appreciated that reference herein to
a height can be reference to the maximum height measurable of the
abrasive particle 300. It will be described later that the abrasive
particle 300 may have different heights at different positions
within the body 301 of the abrasive particle 300.
[0092] In addition to the primary aspect ratio, the abrasive
particle 300 can be formed such that the body 301 comprises a
secondary aspect ratio, which can be defined as a ratio of
length:height, wherein the height is an interior median height
(Mhi). In certain instances, the secondary aspect ratio can be at
least about 1:1, such as at least about 2:1, at least about 4:1, or
even at least about 5:1. Still, in other instances, the abrasive
particle 300 can be formed such that the body 301 has a secondary
aspect ratio that is not greater than about 1:3, such as not
greater than 1:2, or even not greater than about 1:1. It will be
appreciated that the body 301 can have a secondary aspect ratio
within a range between any of the ratios noted above, such as
within a range between about 5:1 and about 1:1.
[0093] In accordance with another embodiment, the abrasive particle
300 can be formed such that the body 301 comprises a tertiary
aspect ratio, defined by the ratio width:height, wherein the height
is an interior median height (Mhi). The tertiary aspect ratio of
the body 301 can be can be at least about 1:1, such as at least
about 2:1, at least about 4:1, at least about 5:1, or even at least
about 6:1. Still, in other instances, the abrasive particle 300 can
be formed such that the body 301 has a tertiary aspect ratio that
is not greater than about 3:1, such as not greater than 2:1, or
even not greater than about 1:1. It will be appreciated that the
body 301 can have a tertiary aspect ratio within a range between
any of the ratios noted above, such as within a range between about
6:1 and about 1:1.
[0094] According to one embodiment, the body 301 of the shaped
abrasive particle 300 can have particular dimensions, which may
facilitate improved performance. For example, in one instance, the
body 301 can have an interior height (hi), which can be the
smallest dimension of height of the body 301 as measured along a
dimension between any corner and opposite midpoint edge on the body
301. In particular instances, wherein the body 301 is a generally
triangular two-dimensional shape, the interior height (hi) may be
the smallest dimension of height (i.e., measure between the bottom
surface 304 and the upper surface 305) of the body 301 for three
measurements taken between each of the three corners and the
opposite midpoint edges. The interior height (hi) of the body 301
of a shaped abrasive particle 300 is illustrated in FIG. 3B.
According to one embodiment, the interior height (hi) can be at
least about 20% of the width (w). The height (hi) may be measured
by sectioning or mounting and grinding the shaped abrasive particle
300 and viewing in a manner sufficient (e.g., light microscope or
SEM) to determine the smallest height (hi) within the interior of
the body 301. In one particular embodiment, the height (hi) can be
at least about 22% of the width, such as at least about 25%, at
least about 30%, or even at least about 33%, of the width of the
body 301. For one non-limiting embodiment, the height (hi) of the
body 301 can be not greater than about 80% of the width of the body
301, such as not greater than about 76%, not greater than about
73%, not greater than about 70%, not greater than about 68% of the
width, not greater than about 56% of the width, not greater than
about 48% of the width, or even not greater than about 40% of the
width. It will be appreciated that the height (hi) of the body 301
can be within a range between any of the above noted minimum and
maximum percentages.
[0095] A batch of shaped abrasive particles, can be fabricated,
wherein the median interior height value (Mhi) can be controlled,
which may facilitate improved performance. In particular, the
median internal height (hi) of a batch can be related to a median
width of the shaped abrasive particles of the batch in the same
manner as described above. Notably, the median interior height
(Mhi) can be at least about 20% of the width, such as at least
about 22%, at least about 25%, at least about 30%, or even at least
about 33% of the median width of the shaped abrasive particles of
the batch. For one non-limiting embodiment, the median interior
height (Mhi) of the body 301 can be not greater than about 80%,
such as not greater than about 76%, not greater than about 73%, not
greater than about 70%, not greater than about 68% of the width,
not greater than about 56% of the width, not greater than about 48%
of the width, or even not greater than about 40% of the median
width of the body 301. It will be appreciated that the median
interior height (Mhi) of the body 301 can be within a range between
any of the above noted minimum and maximum percentages.
[0096] Furthermore, the batch of shaped abrasive particles may
exhibit improved dimensional uniformity as measured by the standard
deviation of a dimensional characteristic from a suitable sample
size. According to one embodiment, the shaped abrasive particles
can have an interior height variation (Vhi), which can be
calculated as the standard deviation of interior height (hi) for a
suitable sample size of particles from a batch. According to one
embodiment, the interior height variation can be not greater than
about 60 microns, such as not greater than about 58 microns, not
greater than about 56 microns, or even not greater than about 54
microns. In one non-limiting embodiment, the interior height
variation (Vhi) can be at least about 2 microns. It will be
appreciated that the interior height variation of the body can be
within a range between any of the above noted minimum and maximum
values.
[0097] For another embodiment, the body 301 of the shaped abrasive
particle 300 can have an interior height (hi) of at least about 400
microns. More particularly, the height may be at least about 450
microns, such as at least about 475 microns, or even at least about
500 microns. In still one non-limiting embodiment, the height of
the body 301 can be not greater than about 3 mm, such as not
greater than about 2 mm, not greater than about 1.5 mm, not greater
than about 1 mm, or even not greater than about 800 microns. It
will be appreciated that the height of the body 301 can be within a
range between any of the above noted minimum and maximum values.
Moreover, it will be appreciated that the above range of values can
be representative of a median interior height (Mhi) value for a
batch of shaped abrasive particles.
[0098] For certain embodiments herein, the body 301 of the shaped
abrasive particle 300 can have particular dimensions, including for
example, a width>length, a length>height, and a
width>height. More particularly, the body 301 of the shaped
abrasive particle 300 can have a width (w) of at least about 600
microns, such as at least about 700 microns, at least about 800
microns, or even at least about 900 microns. In one non-limiting
instance, the body 301 can have a width of not greater than about 4
mm, such as not greater than about 3 mm, not greater than about 2.5
mm, or even not greater than about 2 mm. It will be appreciated
that the width of the body 301 can be within a range between any of
the above noted minimum and maximum values. Moreover, it will be
appreciated that the above range of values can be representative of
a median width (Mw) for a batch of shaped abrasive particles.
[0099] The body 301 of the shaped abrasive particle 300 can have
particular dimensions, including for example, a length (L middle or
Lp) of at least about 0.4 mm, such as at least about 0.6 mm, at
least about 0.8 mm, or even at least about 0.9 mm. Still, for at
least one non-limiting embodiment, the body 301 can have a length
of not greater than about 4 mm, such as not greater than about 3
mm, not greater than about 2.5 mm, or even not greater than about 2
mm. It will be appreciated that the length of the body 301 can be
within a range between any of the above noted minimum and maximum
values. Moreover, it will be appreciated that the above range of
values can be representative of a median length (Ml), which may be
more particularly, a median middle length (MLmiddle) or median
profile length (MLp) for a batch of shaped abrasive particles.
[0100] The shaped abrasive particle 300 can have a body 301 having
a particular amount of dishing, wherein the dishing value (d) can
be defined as a ratio between an average height of the body 301 at
the corners (Ahc) as compared to smallest dimension of height of
the body 301 at the interior (hi). The average height of the body
301 at the corners (Ahc) can be calculated by measuring the height
of the body 301 at all corners and averaging the values, and may be
distinct from a single value of height at one corner (hc). The
average height of the body 301 at the corners or at the interior
can be measured using a STIL (Sciences et Techniques Industrielles
de la Lumiere--France) Micro Measure 3D Surface Profilometer (white
light (LED) chromatic aberration technique). Alternatively, the
dishing may be based upon a median height of the particles at the
corner (Mhc) calculated from a suitable sampling of particles from
a batch. Likewise, the interior height (hi) can be a median
interior height (Mhi) derived from a suitable sampling of shaped
abrasive particles from a batch. According to one embodiment, the
dishing value (d) can be not greater than about 2, such as not
greater than about 1.9, not greater than about 1.8, not greater
than about 1.7, not greater than about 1.6, not greater than about
1.5, or even not greater than about 1.2. Still, in at least one
non-limiting embodiment, the dishing value (d) can be at least
about 0.9, such as at least about 1.0. It will be appreciated that
the dishing ratio can be within a range between any of the minimum
and maximum values noted above. Moreover, it will be appreciated
that the above dishing values can be representative of a median
dishing value (Md) for a batch of shaped abrasive particles.
[0101] The shaped abrasive particles of the embodiments herein,
including for example, the body 301 of the particle of FIG. 3A can
have a bottom surface 304 defining a bottom area (A.sub.b). In
particular instances, the bottom surface 304 can be the largest
surface of the body 301. The bottom major surface 304 can have a
surface area defined as the bottom area (A.sub.b) that is different
than the surface area of the upper major surface 303. In one
particular embodiment, the bottom major surface 304 can have a
surface area defined as the bottom area (A.sub.b) that is different
than the surface area of the upper major surface 303. In another
embodiment, the bottom major surface 304 can have a surface area
defined as the bottom area (A.sub.b) that is less than the surface
area of the upper major surface 303.
[0102] Additionally, the body 301 can have a cross-sectional
midpoint area (A.sub.m) defining an area of a plane perpendicular
to the bottom area (A.sub.b) and extending through a midpoint 381
of the particle 300. In certain instances, the body 301 can have an
area ratio of bottom area to midpoint area (A.sub.b/A.sub.m) of not
greater than about 6. In more particular instances, the area ratio
can be not greater than about 5.5, such as not greater than about
5, not greater than about 4.5, not greater than about 4, not
greater than about 3.5, or even not greater than about 3. Still, in
one non-limiting embodiment, the area ratio may be at least about
1.1, such as at least about 1.3, or even at least about 1.8. It
will be appreciated that the area ratio can be within a range
between any of the minimum and maximum values noted above.
Moreover, it will be appreciated that the above area ratios can be
representative of a median area ratio for a batch of shaped
abrasive particles.
[0103] Furthermore the shaped abrasive particles of the embodiments
herein including, for example, the particle of FIG. 3B, can have a
normalized height difference of not greater than about 0.3. The
normalized height difference can be defined by the absolute value
of the equation [(hc-hm)/(hi)]. In other embodiments, the
normalized height difference can be not greater than about 0.26,
such as not greater than about 0.22, or even not greater than about
0.19. Still, in one particular embodiment, the normalized height
difference can be at least about 0.04, such as at least about 0.05,
or even at least about 0.06. It will be appreciated that the
normalized height difference can be within a range between any of
the minimum and maximum values noted above. Moreover, it will be
appreciated that the above normalized height values can be
representative of a median normalized height value for a batch of
shaped abrasive particles.
[0104] In another instance, the body 301 can have a profile ratio
of at least about 0.04, wherein the profile ratio is defined as a
ratio of the average difference in height [hc-hm] to the length
(Lmiddle) of the shaped abrasive particle 300, defined as the
absolute value of [(hc-hm)/(Lmiddle)]. It will be appreciated that
the length (Lmiddle) of the body 301 can be the distance across the
body 301 as illustrated in FIG. 3B. Moreover, the length may be an
average or median length calculated from a suitable sampling of
particles from a batch of shaped abrasive particles as defined
herein. According to a particular embodiment, the profile ratio can
be at least about 0.05, at least about 0.06, at least about 0.07,
at least about 0.08, or even at least about 0.09. Still, in one
non-limiting embodiment, the profile ratio can be not greater than
about 0.3, such as not greater than about 0.2, not greater than
about 0.18, not greater than about 0.16, or even not greater than
about 0.14. It will be appreciated that the profile ratio can be
within a range between any of the minimum and maximum values noted
above. Moreover, it will be appreciated that the above profile
ratio can be representative of a median profile ratio for a batch
of shaped abrasive particles.
[0105] According to another embodiment, the body 301 can have a
particular rake angle, which may be defined as an angle between the
bottom surface 304 and a side surface 305, 306 or 307 of the body
301. For example, the rake angle may be within a range between
about 1.degree. and about 80.degree.. For other particles herein,
the rake angle can be within a range between about 5.degree. and
55.degree., such as between about 10.degree. and about 50.degree.,
between about 15.degree. and 50.degree., or even between about
20.degree. and 50.degree.. Formation of an abrasive particle having
such a rake angle can improve the abrading capabilities of the
abrasive particle 300. Notably, the rake angle can be within a
range between any two rake angles noted above.
[0106] According to another embodiment, the shaped abrasive
particles herein including, for example, the particles of FIGS. 3A
and 3B, can have an ellipsoidal region 317 in the upper surface 303
of the body 301. The ellipsoidal region 317 can be defined by a
trench region 318 that can extend around the upper surface 303 and
define the ellipsoidal region 317. The ellipsoidal region 317 can
encompass the midpoint 381. Moreover, it is thought that the
ellipsoidal region 317 defined in the upper surface 303 can be an
artifact of the forming process, and may be formed as a result of
the stresses imposed on the mixture 101 during formation of the
shaped abrasive particles according to the methods described
herein.
[0107] The shaped abrasive particle 300 can be formed such that the
body 301 includes a crystalline material, and more particularly, a
polycrystalline material. Notably, the polycrystalline material can
include abrasive grains. In one embodiment, the body 301 can be
essentially free of an organic material, including for example, a
binder. More particularly, the body 301 can consist essentially of
a polycrystalline material.
[0108] In one aspect, the body 301 of the shaped abrasive particle
300 can be an agglomerate including a plurality of abrasive
particles, grit, and/or grains bonded to each other to form the
body 301 of the abrasive particle 300. Suitable abrasive grains can
include nitrides, oxides, carbides, borides, oxynitrides,
oxyborides, diamond, and a combination thereof. In particular
instances, the abrasive grains can include an oxide compound or
complex, such as aluminum oxide, zirconium oxide, titanium oxide,
yttrium oxide, chromium oxide, strontium oxide, silicon oxide, and
a combination thereof. In one particular instance, the abrasive
particle 300 is formed such that the abrasive grains forming the
body 301 include alumina, and more particularly, may consist
essentially of alumina. Moreover, in particular instances, the
shaped abrasive particle 300 can be formed from a seeded
sol-gel.
[0109] The abrasive grains (i.e., crystallites) contained within
the body 301 may have an average grain size that is generally not
greater than about 100 microns. In other embodiments, the average
grain size can be less, such as not greater than about 80 microns,
not greater than about 50 microns, not greater than about 30
microns, not greater than about 20 microns, not greater than about
10 microns, or even not greater than about 1 micron. Still, the
average grain size of the abrasive grains contained within the body
301 can be at least about 0.01 microns, such as at least about 0.05
microns, such as at least about 0.08 microns, at least about 0.1
microns, or even at least about 0.5 microns. It will be appreciated
that the abrasive grains can have an average grain size within a
range between any of the minimum and maximum values noted
above.
[0110] In accordance with certain embodiments, the abrasive
particle 300 can be a composite article including at least two
different types of abrasive grains within the body 301. It will be
appreciated that different types of abrasive grains are abrasive
grains having different compositions with regard to each other. For
example, the body 301 can be formed such that is includes at least
two different types of abrasive grains, wherein the two different
types of abrasive grains can be nitrides, oxides, carbides,
borides, oxynitrides, oxyborides, diamond, and a combination
thereof.
[0111] In accordance with an embodiment, the abrasive particle 300
can have an average particle size, as measured by the largest
dimension measurable on the body 301, of at least about 100
microns. In fact, the abrasive particle 300 can have an average
particle size of at least about 150 microns, such as at least about
200 microns, at least about 300 microns, at least about 400
microns, at least about 500 microns, at least about 600 microns, at
least about 700 microns, at least about 800 microns, or even at
least about 900 microns. Still, the abrasive particle 300 can have
an average particle size that is not greater than about 5 mm, such
as not greater than about 3 mm, not greater than about 2 mm, or
even not greater than about 1.5 mm. It will be appreciated that the
abrasive particle 300 can have an average particle size within a
range between any of the minimum and maximum values noted
above.
[0112] The shaped abrasive particles of the embodiments herein can
have a percent flashing that may facilitate improved performance.
Notably, the flashing defines an area of the particle as viewed
along one side, such as illustrated in FIG. 4, wherein the flashing
extends from a side surface of the body 301 within the boxes 402
and 403. The flashing can represent tapered regions proximate to
the upper surface 303 and bottom surface 304 of the body 301. The
flashing can be measured as the percentage of area of the body 301
along the side surface contained within a box extending between an
innermost point of the side surface (e.g., 421) and an outermost
point (e.g., 422) on the side surface of the body 301. In one
particular instance, the body 301 can have a particular content of
flashing, which can be the percentage of area of the body 301
contained within the boxes 402 and 403 compared to the total area
of the body 301 contained within boxes 402, 403, and 404. According
to one embodiment, the percent flashing (f) of the body 301 can be
at least about 1%. In another embodiment, the percent flashing can
be greater, such as at least about 2%, at least about 3%, at least
about 5%, at least about 8%, at least about 10%, at least about
12%, such as at least about 15%, at least about 18%, or even at
least about 20%. Still, in a non-limiting embodiment, the percent
flashing of the body 301 can be controlled and may be not greater
than about 45%, such as not greater than about 40%, not greater
than about 35%, not greater than about 30%, not greater than about
25%, not greater than about 20%, not greater than about 18%, not
greater than about 15%, not greater than about 12%, not greater
than about 10%, not greater than about 8%, not greater than about
6%, or even not greater than about 4%. It will be appreciated that
the percent flashing of the body 301 can be within a range between
any of the above minimum and maximum percentages. Moreover, it will
be appreciated that the above flashing percentages can be
representative of an average flashing percentage or a median
flashing percentage for a batch of shaped abrasive particles.
[0113] The percent flashing can be measured by mounting the shaped
abrasive particle 300 on its side and viewing the body 301 at the
side to generate a black and white image, such as illustrated in
FIG. 4. A suitable program for such includes ImageJ software. The
percentage flashing can be calculated by determining the area of
the body 301 in the boxes 402 and 403 compared to the total area of
the body 301 as viewed at the side (total shaded area), including
the area in the center 404 and within the boxes. Such a procedure
can be completed for a suitable sampling of particles to generate
average, median, and/or and standard deviation values.
[0114] A batch of shaped abrasive particles according to
embodiments herein may exhibit improved dimensional uniformity as
measured by the standard deviation of a dimensional characteristic
from a suitable sample size. According to one embodiment, the
shaped abrasive particles can have a flashing variation (Vf), which
can be calculated as the standard deviation of flashing percentage
(f) for a suitable sample size of particles from a batch. According
to one embodiment, the flashing variation can be not greater than
about 5.5%, such as not greater than about 5.3%, not greater than
about 5%, or not greater than about 4.8%, not greater than about
4.6%, or even not greater than about 4.4%. In one non-limiting
embodiment, the flashing variation (Vf) can be at least about 0.1%.
It will be appreciated that the flashing variation can be within a
range between any of the minimum and maximum percentages noted
above.
[0115] The shaped abrasive particles of the embodiments herein can
have a height (hi) and flashing multiplier value (hiF) of at least
4000, wherein hiF=(hi)(f), an "hi" represents a minimum interior
height of the body 301 as described above and "f" represents the
percent flashing. In one particular instance, the height and
flashing multiplier value (hiF) of the body 301 can be greater,
such as at least about 4500 micron %, at least about 5000 micron %,
at least about 6000 micron %, at least about 7000 micron %, or even
at least about 8000 micron %. Still, in one non-limiting
embodiment, the height and flashing multiplier value can be not
greater than about 45000 micron %, such as not greater than about
30000 micron %, not greater than about 25000 micron %, not greater
than about 20000 micron %, or even not greater than about 18000
micron %. It will be appreciated that the height and flashing
multiplier value of the body 301 can be within a range between any
of the above minimum and maximum values. Moreover, it will be
appreciated that the above multiplier value can be representative
of a median multiplier value (MhiF) for a batch of shaped abrasive
particles.
[0116] Coated Abrasive Article
[0117] After forming or sourcing the shaped abrasive particle 300,
the particles may be combined with a backing to form a coated
abrasive article. In particular, the coated abrasive article may
utilize a plurality of shaped abrasive particles, which can be
dispersed in a single layer and overlying the backing.
[0118] As illustrated in FIG. 5, the coated abrasive 500 can
include a substrate 501 (i.e., a backing) and at least one adhesive
layer overlying a surface of the substrate 501. The adhesive layer
can include a make coat 503 and/or a size coat 504. The coated
abrasive 500 can include abrasive particulate material 510, which
can include shaped abrasive particles 505 of the embodiments herein
and a second type of abrasive particulate material 507 in the form
of diluent abrasive particles having a random shape, which may not
necessarily be shaped abrasive particles. The make coat 503 can be
overlying the surface of the substrate 501 and surrounding at least
a portion of the shaped abrasive particles 505 and second type of
abrasive particulate material 507. The size coat 504 can be
overlying and bonded to the shaped abrasive particles 505 and
second type of abrasive particulate material 507 and the make coat
503.
[0119] According to one embodiment, the substrate 501 can include
an organic material, inorganic material, and a combination thereof.
In certain instances, the substrate 501 can include a woven
material. However, the substrate 501 may be made of a non-woven
material. Particularly suitable substrate materials can include
organic materials, including polymers, and particularly, polyester,
polyurethane, polypropylene, polyimides such as KAPTON from DuPont,
paper. Some suitable inorganic materials can include metals, metal
alloys, and particularly, foils of copper, aluminum, steel, and a
combination thereof.
[0120] A polymer formulation may be used to form any of a variety
of layers of the abrasive article such as, for example, a
frontfill, a pre-size, the make coat, the size coat, and/or a
supersize coat. When used to form the frontfill, the polymer
formulation generally includes a polymer resin, fibrillated fibers
(preferably in the form of pulp), filler material, and other
optional additives. Suitable formulations for some frontfill
embodiments can include material such as a phenolic resin,
wollastonite filler, defoamer, surfactant, a fibrillated fiber, and
a balance of water. Suitable polymeric resin materials include
curable resins selected from thermally curable resins including
phenolic resins, urea/formaldehyde resins, phenolic/latex resins,
as well as combinations of such resins. Other suitable polymeric
resin materials may also include radiation curable resins, such as
those resins curable using electron beam, UV radiation, or visible
light, such as epoxy resins, acrylated oligomers of acrylated epoxy
resins, polyester resins, acrylated urethanes and polyester
acrylates and acrylated monomers including monoacrylated,
multiacrylated monomers. The formulation can also comprise a
nonreactive thermoplastic resin binder which can enhance the
self-sharpening characteristics of the deposited abrasive
composites by enhancing the erodability. Examples of such
thermoplastic resin include polypropylene glycol, polyethylene
glycol, and polyoxypropylene-polyoxyethene block copolymer, etc.
Use of a frontfill on the substrate 501 can improve the uniformity
of the surface, for suitable application of the make coat 503 and
improved application and orientation of shaped abrasive particles
505 in a predetermined orientation.
[0121] The make coat 503 can be applied to the surface of the
substrate 501 in a single process, or alternatively, the abrasive
particulate material 510 can be combined with a make coat 503
material and applied as a mixture to the surface of the substrate
501. Suitable materials of the make coat 503 can include organic
materials, particularly polymeric materials, including for example,
polyesters, epoxy resins, polyurethanes, polyamides, polyacrylates,
polymethacrylates, polyvinyl chlorides, polyethylene, polysiloxane,
silicones, cellulose acetates, nitrocellulose, natural rubber,
starch, shellac, and mixtures thereof. In one embodiment, the make
coat 503 can include a polyester resin. The coated substrate can
then be heated in order to cure the resin and the abrasive
particulate material to the substrate. In general, the coated
substrate 501 can be heated to a temperature of between about
100.degree. C. to less than about 250.degree. C. during this curing
process.
[0122] The abrasive particulate material 510 can include shaped
abrasive particles 505 according to embodiments herein. In
particular instances, the abrasive particulate material 510 may
include different types of shaped abrasive particles 505. The
different types of shaped abrasive particles can differ from each
other in composition, in two-dimensional shape, in
three-dimensional shape, in size, and a combination thereof as
described in the embodiments herein. As illustrated, the coated
abrasive 500 can include a shaped abrasive particle 505 having a
generally triangular two-dimensional shape.
[0123] The other type of abrasive particles 507 can be diluent
particles different than the shaped abrasive particles 505. For
example, the diluent particles can differ from the shaped abrasive
particles 505 in composition, in two-dimensional shape, in
three-dimensional shape, in size, and a combination thereof. For
example, the abrasive particles 507 can represent conventional,
crushed abrasive grit having random shapes. The abrasive particles
507 may have a median particle size less than the median particle
size of the shaped abrasive particles 505.
[0124] After sufficiently forming the make coat 503 with the
abrasive particulate material 510, the size coat 504 can be formed
to overlie and bond the abrasive particulate material 510 in place.
The size coat 504 can include an organic material, may be made
essentially of a polymeric material, and notably, can use
polyesters, epoxy resins, polyurethanes, polyamides, polyacrylates,
polymethacrylates, poly vinyl chlorides, polyethylene,
polysiloxane, silicones, cellulose acetates, nitrocellulose,
natural rubber, starch, shellac, and mixtures thereof.
[0125] According to one embodiment, the shaped abrasive particles
505 herein can be oriented in a predetermined orientation relative
to each other and the substrate 501. While not completely
understood, it is thought that one or a combination of dimensional
features are responsible for the improved positioning of the shaped
abrasive particles 505. According to one embodiment, the shaped
abrasive particles 505 can be oriented in a flat orientation
relative to the substrate 501, such as that shown in FIG. 5. In the
flat orientation, the bottom surface 304 of the shaped abrasive
particles can be closest to a surface of the substrate 501 (i.e.,
the backing) and the upper surface 303 of the shaped abrasive
particles 505 can be directed away from the substrate 501 and
configured to conduct initial engagement with a workpiece.
[0126] According to another embodiment, the shaped abrasive
particles 505 can be placed on a substrate 501 in a predetermined
side orientation, such as that shown in FIG. 6. In particular
instances, a majority of the shaped abrasive particles 505 of the
total content of shaped abrasive particles 505 on the abrasive
article 500 can have a predetermined and side orientation. In the
side orientation, the bottom surface 304 of the shaped abrasive
particles 505 can be spaced away and angled relative to the surface
of the substrate 501. In particular instances, the bottom surface
304 can form an obtuse angle (A) relative to the surface of the
substrate 501. Moreover, the upper surface 303 is spaced away and
angled relative to the surface of the substrate 501, which in
particular instances, may define a generally acute angle (B). In a
side orientation, a side surface (305, 306, or 307) can be closest
to the surface of the substrate 501, and more particularly, may be
in direct contact with a surface of the substrate 501.
[0127] For certain other abrasive articles herein, at least about
55% of the plurality of shaped abrasive particles 505 on the
abrasive article 500 can have a predetermined side orientation.
Still, the percentage may be greater, such as at least about 60%,
at least about 65%, at least about 70%, at least about 75%, at
least about 77%, at least about 80%, at least about 81%, or even at
least about 82%. And for one non-limiting embodiment, an abrasive
article 500 may be formed using the shaped abrasive particles 505
herein, wherein not greater than about 99% of the total content of
shaped abrasive particles have a predetermined side
orientation.
[0128] To determine the percentage of particles in a predetermined
orientation, a 2D microfocus x-ray image of the abrasive article
500 is obtained using a CT scan machine run in the conditions of
Table 1 below. The X-ray 2D imaging was conducted on RB214 with
Quality Assurance software. A specimen mounting fixture utilizes a
plastic frame with a 4''.times.4'' window and an O0.5'' solid
metallic rod, the top part of which is half flattened with two
screws to fix the frame. Prior to imaging, a specimen was clipped
over one side of the frame where the screw heads were faced with
the incidence direction of the X-rays. Then five regions within the
4''.times.4'' window area are selected for imaging at 120 kV/80
.mu.A. Each 2D projection was recorded with the X-ray off-set/gain
corrections and at a magnification of 15 times.
TABLE-US-00001 TABLE 1 Field of view Voltage Current per image (kV)
(.mu.A) Magnification (mm .times. mm) Exposure time 120 80 15X 16.2
.times. 13.0 500 ms/2.0 fps
[0129] The image is then imported and analyzed using the ImageJ
program, wherein different orientations are assigned values
according to Table 2 below. FIG. 16 includes images representative
of portions of a coated abrasive according to an embodiment and
used to analyze the orientation of shaped abrasive particles on the
backing.
TABLE-US-00002 TABLE 2 Cell marker type Comments 1 Grains on the
perimeter of the image, partially exposed - standing up 2 Grains on
the perimeter of the image, partially exposed - down 3 Grains on
the image, completely exposed - standing vertical 4 Grains on the
image, completely exposed - down 5 Grains on the image, completely
exposed - standing slanted (between standing vertical and down)
[0130] Three calculations are then performed as provided below in
Table 3. After conducting the calculations, the percentage of
grains in a particular orientation (e.g., side orientation) per
square centimeter can be derived.
TABLE-US-00003 TABLE 3 5) Parameter Protocol* % grains up ((0.5
.times. 1) + 3 + 5)/ (1 + 2 + 3 + 4 + 5) Total # of grains per
cm.sup.2 (1 + 2 + 3 + 4 + 5) # of grains up per cm.sup.2 (% grains
up .times. Total # of grains per cm.sup.2 *These are all normalized
with respect to the representative area of the image. + - A scale
factor of 0.5 was applied to account for the fact that they are not
completely present in the image.
[0131] Furthermore, the abrasive articles made with the shaped
abrasive particles can utilize various contents of the shaped
abrasive particles. For example, the abrasive articles can be
coated abrasive articles including a single layer of the shaped
abrasive particles in an open-coat configuration or a closed-coat
configuration. For example, the plurality of shaped abrasive
particles can define an open-coat abrasive product having a coating
density of shaped abrasive particles of not greater than about 70
particles/cm.sup.2. In other instances, the density of shaped
abrasive particle per square centimeter of the open-coat abrasive
article may be not greater than about 65 particles/cm.sup.2, such
as not greater than about 60 particles/cm.sup.2, not greater than
about 55 particles/cm.sup.2, or even not greater than about 50
particles/cm.sup.2. Still, in one non-limiting embodiment, the
density of the open-coat coated abrasive using the shaped abrasive
particle herein can be at least about 5 particles/cm.sup.2, or even
at least about 10 particles/cm.sup.2. It will be appreciated that
the density of shaped abrasive particles per square centimeter of
an open-coat coated abrasive article can be within a range between
any of the above minimum and maximum values.
[0132] In an alternative embodiment, the plurality of shaped
abrasive particles can define a closed-coat abrasive product having
a coating density of shaped abrasive particles of at least about 75
particles/cm.sup.2, such as at least about 80 particles/cm.sup.2,
at least about 85 particles/cm.sup.2, at least about 90
particles/cm.sup.2, at least about 100 particles/cm.sup.2. Still,
in one non-limiting embodiment, the density of the closed-coat
coated abrasive using the shaped abrasive particle herein can be
not greater than about 500 particles/cm.sup.2. It will be
appreciated that the density of shaped abrasive particles per
square centimeter of the closed-coat abrasive article can be within
a range between any of the above minimum and maximum values.
[0133] In certain instances, the abrasive article can have an
open-coat density of a coating not greater than about 50% of
abrasive particle covering the exterior abrasive surface of the
article. In other embodiments, the percentage coating of the
abrasive particles relative to the total area of the abrasive
surface can be not greater than about 40%, not greater than about
30%, not greater than about 25%, or even not greater than about
20%. Still, in one non-limiting embodiment, the percentage coating
of the abrasive particles relative to the total area of the
abrasive surface can be at least about 5%, such as at least about
10%, at least about 15%, at least about 20%, at least about 25%, at
least about 30%, at least about 35%, or even at least about 40%. It
will be appreciated that the percent coverage of shaped abrasive
particles for the total area of abrasive surface can be within a
range between any of the above minimum and maximum values.
[0134] Some abrasive articles may have a particular content of
abrasive particles for a length (e.g., ream) of the backing or the
substrate 501. For example, in one embodiment, the abrasive article
may utilize a normalized weight of shaped abrasive particles of at
least about 20 lbs/ream, such as at least about 25 lbs/ream, or
even at least about 30 lbs/ream. Still, in one non-limiting
embodiment, the abrasive articles can include a normalized weight
of shaped abrasive particles of not greater than about 60 lbs/ream,
such as not greater than about 50 lbs/ream, or even not greater
than about 45 lbs/ream. It will be appreciated that the abrasive
articles of the embodiments herein can utilize a normalized weight
of shaped abrasive particle within a range between any of the above
minimum and maximum values.
[0135] The plurality of shaped abrasive particles on an abrasive
article as described herein can define a first portion of a batch
of abrasive particles, and the features described in the
embodiments herein can represent features that are present in at
least a first portion of a batch of shaped abrasive particles.
Moreover, according to an embodiment, control of one or more
process parameters as already described herein also can control the
prevalence of one or more features of the shaped abrasive particles
of the embodiments herein. The provision of one or more features of
any shaped abrasive particle of a batch may facilitate alternative
or improved deployment of the particles in an abrasive article and
may further facilitate improved performance or use of the abrasive
article.
[0136] The first portion of a batch of abrasive particles may
include a plurality of shaped abrasive particles, wherein each of
the particles of the plurality of shaped abrasive particles can
have substantially the same features, including but not limited to,
for example, the same two-dimensional shape of a major surface.
Other features include any of the features of the embodiments
described herein. The batch may include various contents of the
first portion. The first portion may be a minority portion (e.g.,
less than 50% and any whole number integer between 1% and 49%) of
the total number of particles in a batch, a majority portion (e.g.,
50% or greater and any whole number integer between 50% and 99%) of
the total number of particles of the batch, or even essentially all
of the particles of a batch (e.g., between 99% and 100%). For
example, the first portion of the batch may be present in a
minority amount or majority amount as compared to the total amount
of particles in the batch. In particular instances, the first
portion may be present in an amount of at least about 1%, such as
at least about 5%, at least about 10%, at least about 20%, at least
about 30%, at least about 40%, at least about 50%, at least about
60%, or even at least about 70% for the total content of portions
within the batch. Still, in another embodiment, the batch may
include not greater than about 99%, such as not greater than about
90%, not greater than about 80%, not greater than about 70%, not
greater than about 60%, not greater than about 50%, not greater
than about 40%, not greater than about 30%, not greater than about
20%, not greater than about 10%, not greater than about 8%, not
greater than about 6%, or even not greater than about 4% of the
first portion for the total amount of particles within the batch.
The batch can include a content of the first portion within a range
between any of the minimum and maximum percentages noted above.
[0137] The batch may also include a second portion of abrasive
particles. The second portion of abrasive particles can include
diluent particles. The second portion of the batch can include a
plurality of abrasive particles having at least one abrasive
characteristic distinct from the plurality of shaped abrasive
particles of the first portion, including but not limited to
abrasive characteristics such as two-dimensional shape, average
particle size, particle color, hardness, friability, toughness,
density, specific surface area, aspect ratio, any of the features
of the embodiments herein, and a combination thereof.
[0138] In certain instances, the second portion of the batch can
include a plurality of shaped abrasive particles, wherein each of
the shaped abrasive particles of the second portion can have
substantially the same feature, including but not limited to, for
example, the same two-dimensional shape of a major surface. The
second portion can have one or more features of the embodiments
herein, and the one or more features of the particles of the second
portion can be distinct compared to the plurality of shaped
abrasive particles of the first portion. In certain instances, the
batch may include a lesser content of the second portion relative
to the first portion, and more particularly, may include a minority
content of the second portion relative to the total content of
particles in the batch. For example, the batch may contain a
particular content of the second portion, including for example,
not greater than about 40%, such as not greater than about 30%, not
greater than about 20%, not greater than about 10%, not greater
than about 8%, not greater than about 6%, or even not greater than
about 4% for the total content of particles in the batch. Still, in
at least one non-limiting embodiment, the batch may contain at
least about 0.5%, such as at least about 1%, at least about 2%, at
least about 3%, at least about 4%, at least about 10%, at least
about 15%, or even at least about 20% of the second portion for the
total content of particles within the batch. It will be appreciated
that the batch can contain a content of the second portion within a
range between any of the minimum and maximum percentages noted
above.
[0139] Still, in an alternative embodiment, the batch may include a
greater content of the second portion relative to the first
portion, and more particularly, can include a majority content of
the second portion for the total content of particles in the batch.
For example, in at least one embodiment, the batch may contain at
least about 55%, such as at least about 60%, of the second portion
for the total content of particles of the batch.
[0140] It will be appreciated that the batch can include additional
portions, including for example a third portion, comprising a
plurality of shaped abrasive particles having a third feature that
can be distinct from the features shared by the particles of either
or both of the first and second portions. The batch may include
various contents of the third portion relative to the second
portion and/or first portion. The third portion may be present in
the batch a minority amount or majority amount for the total number
of particles of the third portion compared to the total number of
particles in the batch. In particular instances, the third portion
may be present in an amount of not greater than about 40%, such as
not greater than about 30%, not greater than about 20%, not greater
than about 10%, not greater than about 8%, not greater than about
6%, or even not greater than about 4% of the total particles within
the batch. Still, in other embodiments the batch may include a
minimum content of the third portion, such as at least about 1%,
such as at least about 5%, at least about 10%, at least about 20%,
at least about 30%, at least about 40%, or even at least about 50%
of the third portion for the total particles within the batch. The
batch can include a content of the third portion within a range
between any of the minimum and maximum percentages noted above.
Moreover, the batch may include a content of diluent, randomly
shaped abrasive particles, which may be present in an amount that
is the same as any of the portions of the embodiments herein.
[0141] According to another aspect, the first portion of the batch
can have a predetermined classification characteristic selected
from the group consisting of average particle shape, average
particle size, particle color, hardness, friability, toughness,
density, specific surface area, major surface corner radius of
curvature, side surface corner radius of curvature, a ratio of
major surface corner radius of curvature and side surface corner
radius of curvature and a combination thereof. Likewise, any of the
other portions of the batch may be classified according to the
above noted classification characteristics.
[0142] FIG. 7A includes a top-view illustration of a major surface
of a shaped abrasive particle according to an embodiment. As
illustrated, the body 701 of the shaped abrasive particle includes
a major surface 702, which can represent the upper major surface or
lower major surface of the body 701. As further illustrated, the
body 701 can have a generally triangular two-dimensional shape.
Moreover, the body 701 can include a corner 703 having a particular
radius of curvature defined by a radius of a best-fit circle
relative to the curvature of the corner 703. The body 701 may
include a major surface corner radius of curvature, which may be
calculated from a single corner or as an average of the radius of
curvature of all the corners of a single major surface of a shaped
abrasive particle (e.g., three corners of the major surface of the
body 701). Additionally, the major surface corner radius of
curvature value may be an average value from a statistically
relevant sample size of shaped abrasive particles of a batch.
Radius of curvature of the corners is calculated on optical images
taken with an Olympus DSX microscope. The particle is viewed from a
suitable orientation (i.e., top-down to view the major surface
corners and from the side to evaluate the side corners) and using
computer software equipped on the microscope, a best-fit circle is
created in the corner to be measured. The best-fit circle is
created such that the maximum length of curvature of a corner
corresponds to a maximum length of the circumference of the
best-fit circle. The radius of the best-fit circle defines the
radius of curvature of the corner.
[0143] The shaped abrasive particles of the embodiments herein can
have a particular major surface corner radius of curvature that may
facilitate certain performance properties. In accordance with an
embodiment, the major surface corner radius of curvature can be at
least about 100 microns, such as at least about 120 microns, at
least about 140 microns, at least about 160 microns, at least about
180 microns, such as at least about 190 microns, at least about 200
microns, at least about 210 microns, at least about 220 microns, at
least about 230 microns, at least about 240 microns, at least about
250 microns, at least about 260 microns, at least about 270
microns, at least about 280 microns, or even at least about 290
microns. Still, the major surface corner radius of curvature for
the body can be not greater than about 800 microns, such as not
greater than about 700 microns, such as not greater than about 600
microns, not greater than about 500 microns, or even not greater
than about 400 microns. It will be appreciated that the shaped
abrasive particles of the embodiments herein may have a body having
a major surface corner radius of curvature within a range between
any of the minimum and maximum values noted above.
[0144] In yet another embodiment, the shaped abrasive particles of
the embodiments herein can have a body having a particular side
surface corner radius of curvature. FIG. 7B includes a side view of
a shaped abrasive particle according to an embodiment. The body 701
can have a major surface 702, a major surface 713 opposite the
major surface 702, and a side surface 705 extending between the
major surfaces 702 and 703. As further illustrated, the body 701
can have a first side surface corner 706 defining an edge between
one of the major surfaces (e.g., the major surface 713) and the
side surface 705. The corner 706 can have a particular radius of
curvature defined by a radius of a best-fit circle relative to the
curvature of the corner 706. The body 701 may include a side
surface corner radius of curvature, which may be calculated from a
single corner of the body 701 or as an average of the radius of
curvature of all the corners defining a corner between one or more
major surfaces and one or more side surfaces of the body 701 of the
shaped abrasive particle. Additionally, the side surface corner
radius of curvature value may be an average value from a
statistically relevant sample size of shaped abrasive particles of
a batch.
[0145] The shaped abrasive particles of the embodiments herein can
have a particular side surface corner radius of curvature that may
facilitate certain performance properties. In accordance with an
embodiment, the side surface corner radius of curvature can be not
greater than about 800 microns, such as not greater than about 700
microns, not greater than about 600 microns, not greater than about
500 microns, not greater than about 400 microns, not greater than
about 300 microns, not greater than about 200 microns, not greater
than about 280 microns, not greater than about 260 microns, not
greater than about 240 microns, not greater than about 220 microns,
not greater than about 200 microns, not greater than about 180
microns, not greater than about 160 microns, not greater than about
140 microns, not greater than about 100 microns, not greater than
about 80 microns, or even not greater than about 60 microns. Still,
it will be appreciated that the body may have a side surface corner
radius of curvature that is at least about 1 micron, such as at
least about 3 microns, at least about 6 microns, at least about 10
microns, at least about 12 microns, at least about 15 microns, at
least about 20 microns, or even at least about 25 microns. It will
be appreciated that the shaped abrasive particles herein can have a
body having a side surface corner radius of curvature within a
range between any of the minimum and maximum values noted
above.
[0146] The shaped abrasive particles of the embodiments herein can
have a particular relationship between the major surface corner
radius of curvature and side surface corner radius of curvature
that may facilitate certain performance. In one instance, the body
can have a major surface corner radius of curvature that is
different than the side surface corner radius of curvature. For
example, the major surface corner radius of curvature of the body
can be greater than the side surface corner radius of curvature of
the body. In another embodiment, the major surface corner radius of
curvature can be less than the side surface corner radius of
curvature. Still, in one non-limiting embodiment, the major surface
corner radius of curvature can be substantially the same as the
side surface corner radius of curvature.
[0147] Furthermore, the body may have a particular ratio SSCR/MSCR,
which can define a ratio between a side surface corner radius of
curvature (SSCR) to a major surface corner radius of curvature
(MSCR). As noted herein, the ratio may be based upon a single major
surface corner radius of curvature value, a single side surface
corner radius of curvature value, an average major surface corner
radius of curvature value, or an average side surface corner radius
of curvature value. In one particular embodiment, the ratio
(SSCR/MSCR) can be not greater than about 1, such as not greater
than about 0.9, not greater than about 0.8, not greater than about
0.7, not greater than about 0.6, not greater than about 0.5, not
greater than about 0.4, not greater than about 0.2, not greater
than about 0.1, or even not greater than about 0.09. Still, in one
non-limiting embodiment, the body can have a ratio SSCR/MSCR of at
least about 0.001, at least about 0.005, at least about 0.01 It
will be appreciated that the body of the shaped abrasive particles
herein can define a ratio (SSCR/MSCR) that is within a range
between any of the minimum and maximum values noted above.
[0148] Without wishing to be tied to a particular theory, it is
noted that a planar portion 710 of the body 701 on the side surface
705 between the first side surface corner 706 and a second side
surface corner 709 may have a particular length that can facilitate
performance associated with the shaped abrasive particles of the
embodiments herein. Moreover, the planar portion 710 can have a
length along the side surface 705 between the corners 706 and 709
that may be less than or equal to the first side surface corner 706
radius of curvature or second side surface corner 709 radius of
curvature, and such a length may affect grinding performance.
Notably, the length of the planar portion 710 may be controlled to
control the grinding efficiency of the shaped abrasive particle in
the major surface orientation and the side surface orientation. It
is also noted that the first side surface corner 706 radius of
curvature may be the same as, or different from, the second side
surface corner 709 radius of curvature. In another embodiment, the
length of the planar portion 710 can be not greater than about 99%,
such as not greater than about 95%, not greater than about 90%, not
greater than about 80%, not greater than about 70%, not greater
than about 60%, not greater than about 50%, not greater than about
40%, not greater than about 30%, not greater than about 20%, not
greater than about 10%, not greater than about 8%, not greater than
about 6%, or even not greater than about 4% of the radius of
curvature of a side surface corner radius of curvature. In another
non-limiting embodiment, the planar portion 710 can have a length
of at least about 1%, such as at least about 5%, at least about
10%, at least about 20%, at least about 30%, at least about 40%, at
least about 50%, at least about 60%, or even at least about 70% of
the radius of curvature of at least one side surface corner radius
of curvature. It will be appreciated, that the planar portion 710
can have a length relative to the average side surface corner
radius of curvature obtained from averaging the radius of curvature
of two or more side surface corners.
[0149] In one aspect, a shaped abrasive particle according the
embodiments herein can have a particular grinding performance
associated with a particular grinding orientation, which can be
measured according to a standardized single grit grinding test
(SGGT). In conducting the SGGT, one single shaped abrasive particle
is held in a grit holder by a bonding material of epoxy. The shaped
abrasive particle is secured in the desired orientation (i.e.,
major surface orientation or side surface orientation) and moved
across a workpiece of 304 stainless steel for a scratch length of 8
inches using a wheel speed of 22 m/s and an initial scratch depth
of 30 microns. The shaped abrasive particle produces a groove in
the workpiece having a cross-sectional area (A.sub.R). For each
sample set, each shaped abrasive particle completes 15 passes
across the 8 inch length, 10 individual particles are tested for
each of the orientation and the results are analyzed. The test
measures the tangential force exerted by the grit on the workpiece,
in the direction that is parallel to the surface of the workpiece
and the direction of the groove, and the net change in the
cross-sectional area of the groove from beginning to the end of the
scratch length is measured to determine the shaped abrasive
particle wear. The net change in the cross-sectional area of the
groove for each pass can be measured. For the SGGT, a minimum
threshold value of at least 1000 microns for the cross-sectional
area of the groove is set for each pass. If the particle fails to
form a groove having the minimum threshold cross-sectional area,
the data is not recorded for that pass.
[0150] The SGGT is conducted using two different orientations of
the shaped abrasive particles relative to the workpiece. The SGGT
is conducted with a first sample set of shaped abrasive particles
in a major surface orientation, wherein a major surface of each
shaped abrasive particle is oriented perpendicular to the grinding
direction and such that the major surface initiates grinding on the
workpiece. The results of the SGGT using the sample set of shaped
abrasive particles in a major surface orientation allows for
measurement of the grinding efficiency of the shaped abrasive
particles in a major surface orientation and calculation of a major
surface grinding efficiency upper quartile value (MSUQ), a major
surface grinding efficiency median value (MSM), and a major surface
grinding efficiency lower quartile value (MSLQ).
[0151] The SGGT is also conducted with a second sample set of
shaped abrasive particles in a side surface orientation, wherein a
side surface of each shaped abrasive particle is oriented
perpendicular to the grinding direction and such that the side
surface initiates grinding of the workpiece. The results of the
SGGT test using the sample set of shaped abrasive particles in a
side orientation allows for measurement of the grinding efficiency
of the shaped abrasive particles in a side orientation and
calculation of a side surface grinding efficiency upper quartile
value (SSUQ), a side surface grinding efficiency median value
(SSM), and a side surface grinding efficiency lower quartile value
(SSLQ).
[0152] FIG. 8 includes a generalized plot of force per total area
removed from the workpiece, which is representative of data derived
from the SGGT. The force per total area removed is a measure of the
grinding efficiency of the shaped abrasive particles, with lower
force per total area removed as an indication of more efficient
grinding performance. As illustrated, FIG. 8 includes a first bar
801 representing SGGT data for the first sample set of shaped
abrasive particles positioned in the major surface orientation, and
thus defining the major surface grinding efficiency upper quartile
value (MSUQ), the major surface grinding efficiency median value
(MSM), and the major surface grinding efficiency lower quartile
value (MSLQ). FIG. 8 also includes a second bar 820 representing
SGGT data for the second sample set of shaped abrasive particles,
where the particles are the same type of particles as used in the
first sample set (i.e., same composition and shape features), but
are tested in the side orientation. As illustrated, the SGGT data
from the second set provides the side surface grinding efficiency
upper quartile value (SSUQ), the side surface grinding efficiency
median value (SSM), and the side surface grinding efficiency lower
quartile value (SSLQ) for the shaped abrasive particles of the
second sample set.
[0153] In accordance with one embodiment, the shaped abrasive
particles herein can have a major surface grinding efficiency
(i.e., MSM) that can be less than the side surface grinding
efficiency (SSM) according to the SGGT. That is, the shaped
abrasive particles of the embodiments herein can have a grinding
efficiency using a major surface that is much better as compared to
the grinding efficiency of the shaped abrasive particles on the
side surface. Still, it will be appreciated, that in other
instances, the shaped abrasive particles of the embodiments herein
can have a SSM that is less than a MSM according to the SGGT.
[0154] In one aspect, the shaped abrasive particles of the
embodiments herein can have a major surface grinding efficiency
upper quartile value (MSUQ), which can be a value defining the
values of force per unit area for lowest 75% of the data points and
excluding the uppermost 25% of values within the data set from
measurements according to the SGGT. In accordance with one
embodiment, the MSUQ can be not greater than about 8.3 kN/mm.sup.2,
such as not greater than about 8 kN/mm.sup.2, not greater than
about 7.8 kN/mm.sup.2, not greater than about 7.5 kN/mm.sup.2, not
greater than about 7.2 kN/mm.sup.2, not greater than about 7
kN/mm.sup.2, not greater than about 6.8 kN/mm.sup.2, not greater
than about 6.5 kN/mm.sup.2, not greater than about 6.2 kN/mm.sup.2,
not greater than about 6 kN/mm.sup.2, not greater than about 5.5
kN/mm.sup.2, not greater than about 5.2 kN/mm.sup.2, or even not
greater than about 4 kN/mm.sup.2. Still, in one non-limiting
embodiment, the MSUQ can be at least about 0.1 kN/mm.sup.2. It will
be appreciated that the MSUQ can be within range between any of the
minimum and maximum values noted above.
[0155] In accordance with another embodiment, the shaped abrasive
particles herein can have a major surface grinding efficiency
median value (MSM), which can define the median value of the major
surface grinding efficiency for the first sample set of shaped
abrasive particles tested according to the SGGT. The MSM can have a
particular value relative to the MSUQ. For example, the MSM can be
less than the MSUQ. In one particular embodiment, the MSM can have
a median value that is not greater than about 8 kN/mm.sup.2, such
as not greater than about 7.8 kN/mm.sup.2, not greater than about
7.5 kN/mm.sup.2, not greater than about 7.2 kN/mm.sup.2, not
greater than about 7 kN/mm.sup.2, not greater than about 6.8
kN/mm.sup.2, not greater than about 6.5 kN/mm.sup.2, not greater
than about 6.2 kN/mm.sup.2, not greater than about 6 kN/mm.sup.2,
not greater than about 5.8 kN/mm.sup.2, not greater than about 5.5
kN/mm.sup.2, not greater than about 5.2 kN/mm.sup.2, not greater
than about 5 kN/mm.sup.2, not greater than about 4.8 kN/mm.sup.2,
not greater than about 4.6 kN/mm.sup.2, not greater than about 4.2
kN/mm.sup.2, not greater than about 4 kN/mm.sup.2, not greater than
about 3.8 kN/mm.sup.2, not greater than about 3.6 kN/mm.sup.2, not
greater than about 3.2 kN/mm.sup.2, not greater than about 3
kN/mm.sup.2, not greater than about 2.8 kN/mm.sup.2, or even not
greater than about 2.6 kN/mm.sup.2. Still, it will be appreciated
that certain shaped abrasive particles herein can have a major
surface grinding efficiency median value (MSM) of at least about
0.1 kN/mm.sup.2. It will be appreciated that the shaped abrasive
particles herein can have a MSM within a range between any of the
minimum and maximum values noted above.
[0156] In yet another embodiment, the shaped abrasive particles
herein can have a particular major surface grinding efficiency
lower quartile value (MSLQ), which can be a value defining the
values of force per unit area for the uppermost 75% of the data
points and excluding the lowest 25% of values within the data set
from measurements according to the SGGT. In at least one
embodiment, the MSLQ can have a relative value compared to the MSM.
For example, the MSLQ can be less than the MSM. In another
embodiment, the MSLQ can be not greater than about 8 kN/mm.sup.2,
such as not greater than about 7 kN/mm.sup.2, not greater than
about 6.5 kN/mm.sup.2, not greater than about 6.2 kN/mm.sup.2, not
greater than about 6 kN/mm.sup.2, not greater than about 5.8
kN/mm.sup.2, not greater than about 5.5 kN/mm.sup.2, not greater
than about 5.2 kN/mm.sup.2, not greater than about 5 kN/mm.sup.2,
not greater than about 4.8 kN/mm.sup.2, not greater than about 4.6
kN/mm.sup.2, not greater than about 4.2 kN/mm.sup.2, not greater
than about 4 kN/mm.sup.2, not greater than about 3.8 kN/mm.sup.2,
not greater than about 3.6 kN/mm.sup.2, not greater than about 3.2
kN/mm.sup.2, not greater than about 3 kN/mm.sup.2, not greater than
about 2.8 kN/mm.sup.2, not greater than about 2.6 kN/mm.sup.2, not
greater than about 2.2 kN/mm.sup.2, not greater than about 2
kN/mm.sup.2, not greater than about 1.9 kN/mm.sup.2. In yet another
embodiment, the MSLQ can be at least about 0.1 kN/mm.sup.2. It will
be appreciated that the shaped abrasive particles herein can have a
MSLQ within any of the minimum and maximum values noted above.
[0157] In yet another embodiment, the shaped abrasive particles
herein can have a particular side surface grinding efficiency upper
quartile value (SSUQ), which can be a value defining the values of
force per unit area for the lowest 75% of the data points,
excluding the upper-most 25% of values within the data set from
measurements according to the SGGT. In accordance with an
embodiment, the SSUQ can be at least about 4.5 kN/mm.sup.2, such as
at least about 5 kN/mm.sup.2, at least about 5.5 kN/mm.sup.2, at
least about 6 kN/mm.sup.2, at least about 6.5 kN/mm.sup.2, at least
about 7 kN/mm.sup.2, at least about 7.5 kN/mm.sup.2, at least about
8 kN/mm.sup.2, at least about 8.5 kN/mm.sup.2, at least about 9
kN/mm.sup.2, at least about 10 kN/mm.sup.2, at least about 15
kN/mm.sup.2, at least about 20 kN/mm.sup.2, or even at least about
25 kN/mm.sup.2. Still, in one non-limiting embodiment, the SSUQ can
be not greater than about 100 kN/mm.sup.2. It will be appreciated
that the shaped abrasive particles herein can have an SSUQ
according to the SSGT that is within a range between any of the
minimum or maximum values noted above.
[0158] In accordance with another embodiment, shaped abrasive
particles herein can have a particular side surface grinding
efficiency median value (SSM), which can be a measure of the median
value of the side surface grinding efficiency as calculated from
the SGGT. The SSM may have a particular value relative to the SSUQ,
and more particularly may be less than the SSUQ. In one particular
embodiment, the shaped abrasive particles herein can have an SSM
that is at least about 3 kN/mm.sup.2, at least about 3.2
kN/mm.sup.2, at least about 3.5 kN/mm.sup.2, at least about 3.7
kN/mm.sup.2, at least about 4 kN/mm.sup.2, at least about 4.2
kN/mm.sup.2, at least about 4.5 kN/mm.sup.2, at least about 4.7
kN/mm.sup.2, at least about 5 kN/mm.sup.2, at least about 5.2
kN/mm.sup.2, at least about 5.5 kN/mm.sup.2, at least about 5.7
kN/mm.sup.2, at least about 6 kN/mm.sup.2, at least about 6.2
kN/mm.sup.2, at least about 6.5 kN/mm.sup.2, at least about 7
kN/mm.sup.2, at least about 8 kN/mm.sup.2, at least about 9
kN/mm.sup.2, at least about 10 kN/mm.sup.2. In still another
embodiment, the shaped abrasive particles herein can have an SSM
that is not greater than about 100 kN/mm.sup.2. It will be
appreciated that the shaped abrasive particles herein can have a
SSM within a range between any of the minimum and maximum values
noted above.
[0159] Additionally, the shaped abrasive particles herein may have
a side surface grinding efficiency lower quartile value (SSLQ),
which can be a value defining the values of force per unit area for
the uppermost 75% of the data point, excluding the lowest 25% of
values within the data set from measurements according to the SGGT.
In accordance with an embodiment, the SSLQ may have a particular
relationship to the SSM, and more particularly may be less that the
SSM. In at least one embodiment, the shaped abrasive particles
herein can have a SSLQ that is at least about 2.5 kN/mm.sup.2, such
as at least about 2.7 kN/mm.sup.2, at least about 3 kN/mm.sup.2, at
least about 3.1 kN/mm.sup.2, at least about 3.3 kN/mm.sup.2, at
least about 3.5 kN/mm.sup.2, at least about 3.6 kN/mm.sup.2, at
least about 3.8 kN/mm.sup.2, at least about 4 kN/mm.sup.2, at least
about 5 kN/mm.sup.2, at least about 6 kN/mm.sup.2. In yet another
embodiment, the shaped abrasive particles herein may have a SSLQ
that is not greater than about 100 kN/mm.sup.2. It will be
appreciated that the shaped abrasive particles herein can have an
SSLQ that is within range between any of the minimum and maximum
values noted above.
[0160] In accordance with one embodiment, the shaped abrasive
particles herein can have a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%. The
MSGPD can describe the percent difference between the major surface
grinding efficiency median value (MSM) and the side surface
grinding efficiency median value (SSM). If the MSM is greater than
the SSM, then the MSGPD is calculated using the equation
MSGPD=[(MSM-SSM)/MSM].times.100%, wherein MSM is greater than SSM.
If the SSM is greater than the MSM, then the MSGPD is calculated
using the equation MSGPD=[(SSM-MSM)/SSM].times.100%. Such a percent
difference in the MSGPD may facilitate particular grinding
performance in fixed abrasive articles. According to one
embodiment, the shaped abrasive particles herein can have a MSGPD
of at least about 42%, such as at least about 44%, at least about
46%, at least about 48%, at least about 50%, at least about 52%, at
least about 54%, at least about 55%, at least about 56%, at least
about 57%, at least about 58%, or even at least about 59%. Still,
in one non-limiting embodiment, the shaped abrasive particle may
have a MSGPD of not greater than about 99%, such as not greater
than about 95%. It will be appreciated that the shaped abrasive
particle may have a MSGPD within a range between any of the minimum
or maximum percentages noted above.
[0161] In yet another embodiment, the shaped abrasive particles
herein can have a major surface grinding efficiency median value
and side surface grinding efficiency median value difference (MSMD)
of at least about 1.9 kN/mm.sup.2. It will be appreciated that the
MSMD may describe the absolute value of the difference between the
MSM and SSM, calculated using the equation MSMD=|MSM-SSM|. In
another embodiment, the MSMD can be at least about 2 kN/mm.sup.2,
such as at least about 2.3 kN/mm.sup.2, at least about 2.5
kN/mm.sup.2, at least about 2.7 kN/mm.sup.2, at least about 3
kN/mm.sup.2, at least about 3.5 kN/mm.sup.2, at least about 4
kN/mm.sup.2, at least about 4.5 kN/mm.sup.2, at least about 5
kN/mm.sup.2, or even at least about 6 kN/mm.sup.2. Still, in one
non-limiting embodiment the MSMD can be not greater than about 50
kN/mm.sup.2. It will be appreciated that the shaped abrasive
particle may have a MSMD within a range between any of the minimum
or maximum percentages noted above.
[0162] In another aspect, the shaped abrasive particles of the
embodiments herein may have a particular maximum quartile-to-median
percent difference (MQMPD). The MQMPD can describe the greatest
percent difference between one of the median values (e.g., the MSM)
and one of the two associated quartile values (i.e., MSUQ, MSLQ,
SSUQ, and SSLQ), and can indicate the greatest variance between a
median value relative to one of the two corresponding quartile
values for the shaped abrasive particles. For example, the MSMPD
for the generalized data set illustrated in FIG. 8 would be based
upon the percent difference between the SSUQ and SSM. Determination
of the MQMPD can include a calculation of the percent difference
for the MSUQ relative to the MSM, the MSLQ relative to the MSM, the
SSUQ relative to the SSM, and the SSLQ relative to the SSM. The
percent difference between of MSUQ relative to MSM is based on the
equation [(MSUQ-MSM)/MSUQ].times.100%. The percent difference
between of MSLQ relative to MSM is based on the equation
[(MSM-MSLQ)/MSM].times.100%. The percent difference between of SSUQ
relative to SSM is based on the equation
[(SSUQ-SSM)/SSUQ].times.100%. The percent difference between of
SSLQ relative to SSM is based on the equation
[(SSM-SSLQ)/SSM].times.100%. Of the foregoing four percent
difference calculations, the percent difference of the greatest
value defines the MQMPD of the SGGT data.
[0163] According to one embodiment, the shaped abrasive particles
herein can have a MQMPD of at least about 48%, such as at least
about 49%, such as at least about 50%, at least about 52%, at least
about 54%, at least about 56%, or even at least about 58%. In yet
another non-limiting embodiment, the shaped abrasive particle may
have a MQMPD of not greater than 99%, or even not greater than
about 95%. It will be appreciated that the shaped abrasive
particles herein can have a MQMPD within a range between any of the
above-noted minimum and maximum percentages. Such a percent
difference in the MSGPD may facilitate particular grinding
performance in fixed abrasive articles.
[0164] In another aspect, the shaped abrasive particles of the
embodiments herein may have a particular maximum quartile
difference (MQD). The MQD can describe the greatest difference
between any of the quartile values (i.e., MSUQ, MSLQ, SSUQ, and
SSLQ), and can indicate the greatest variation between quartiles
for the major orientation or side orientation. For example, the MSD
for the generalized data set illustrated in FIG. 8 would be based
upon the percent difference between the SSUQ and MSLQ, since the
SSUQ has the greatest value of force/area (e.g., kN/mm.sup.2) value
of the quartile values and the MSLQ has the lowest value of
force/area value of the quartile values. In accordance with an
embodiment, the shaped abrasive particles herein can have a MQD of
at least about 6 kN/mm.sup.2, such as least about 6.2 kN/mm.sup.2,
at least about 6.5 kN/mm.sup.2, at least about 6.8 kN/mm.sup.2, at
least about 7 kN/mm.sup.2, at least about 7.5 kN/mm.sup.2, at least
about 8 kN/mm.sup.2, at least about 9 kN/mm.sup.2, at least about
10 kN/mm.sup.2, or even at least about 12 kN/mm.sup.2. In one
non-limiting embodiment, the shaped abrasive particle may have a
MQD of not greater about 100 kN/mm.sup.2. It will be appreciated
that the shaped abrasive particles herein can have a MQD within a
range between any of the above-noted minimum and maximum
values.
[0165] For yet another aspect, the shaped abrasive particles of the
embodiments herein may demonstrate a major surface-to-side surface
quartile percent overlap (MSQPO), which can describe the degree of
overlap between quartiles in the region 830 relative to the maximum
quartile difference, and can indicate the variance in the grinding
efficiency data between the major surface orientation and the side
orientation. For example, the MSQPO for the generalized data set
illustrated in FIG. 8 would be based upon the equation
[(MSUQ-SSLQ)/MQD].times.100%. For shaped abrasive particles of the
embodiments herein, the MSQPO can be not greater than about 11%,
such as not greater than about 10%, not greater than 9%, not
greater than about 8%, not greater than about 7%, not greater than
about 6%, not greater than about 5%, not greater than about 4%, not
greater than about 3%, not greater than about 2%, or even not
greater than about 1%. In one non-limiting embodiment, the shaped
abrasive particle may have a MSQPO of at least about 0.1%. It will
be appreciated that the shaped abrasive particles herein can have a
MSQPO within a range between any of the above-noted minimum and
maximum percentages.
[0166] It will be appreciated that the degree of overlap between
the quartiles may be also be evaluated by calculating the
difference between the upper quartile having the lowest value of
the two upper quartile data points (of either the major surface or
side surface grinding efficiency) and subtracting the value of the
lower quartile grinding efficiency having the greatest value
between the two lower quartile data points, independent of the
orientation. As such, in some instances wherein the upper quartile
and lower quartile values of one data set (e.g., the major surface
orientation) are between the upper quartile and lower quartile
values of the data set for the other orientation (i.e., side
surface orientation) the degree of overlap can be 100% and can be
the difference between the major surface upper quartile and major
surface lower quartile.
[0167] In yet another embodiment, the shaped abrasive particles
herein can have a major surface to side surface upper quartile
percent difference (MSUQPD), which can describe the difference
between the upper quartile value associated with the major surface
grinding efficiency relative to the upper quartile value associated
with the side surface grinding efficiency. For example, the MSUQPD
for the generalized data set illustrated in FIG. 8 would be based
upon the equation [(SSUQ-MSUQ)/SSUQ].times.100%, wherein SSUQ is
greater than MSUQ. If MSUQ were greater than SSUQ, the positions of
the values in the equation are exchanged to provide a positive
percent. In accordance with an embodiment, the MSUQPD can be at
least about 54%, such as at least about 55%, at least about 56%, at
least about 57%, at least about 58%, at least about 60%, at least
about 63%, at least about 65%, or even at least about 70%. In one
non-limiting embodiment, the shaped abrasive particle may have a
MSUQPD of not greater than about 99%. It will be appreciated that
the shaped abrasive particles herein can have a MSUQPD within a
range between any of the above-noted minimum and maximum
percentages.
[0168] According to one aspect, the shaped abrasive particles of
the embodiments herein can have a major surface to side surface
lower quartile percent difference (MSLQPD), which can describe the
difference between the lower quartile value associated with the
major surface grinding efficiency relative to the lower quartile
value associated with the side surface grinding efficiency. For
example, the MSLQPD for the generalized data set illustrated in
FIG. 8 would be based upon the equation
[(SSLQ-MSLQ)/SSLQ].times.100%, wherein SSLQ is greater than MSLQ.
If MSLQ were greater than SSLQ, the positions of the values in the
equation are exchanged to provide a positive percent. In at least
one embodiment, the MSLQPD can be at least about 28%, such as at
least about 30%, at least about 32%, at least about 35%, at least
about 37%, at least about 40%, at least about 42%, at least about
45%, at least about 47%, at least about 50%, at least about 52%, at
least about 55%, or even at least about 57%. In one non-limiting
embodiment, the shaped abrasive particle may have a MSLQPD of not
greater than about 99%. It will be appreciated that the shaped
abrasive particles herein can have a MSLQPD within a range between
any of the above-noted minimum and maximum percentages.
[0169] While reference has been made herein to grinding
characteristics of the shaped abrasive particles according to the
SGGT, it will be appreciated that such values can represent median
values for a batch of abrasive particles, a first portion of a
batch of shaped abrasive particles, or a plurality of shaped
abrasive particles. In particular, it will be appreciated that any
of the characteristics of the embodiments herein, including the
grinding characteristics can be representative of a batch of shaped
abrasive particles. Such grinding characteristics include, but are
not limited to, a major surface grinding efficiency upper quartile
value (MSUQ), a major surface grinding efficiency median value
(MSM), a major surface grinding efficiency lower quartile value
(MSLQ), a side surface grinding efficiency upper quartile value
(SSUQ), a side surface grinding efficiency median value (SSM), a
side surface grinding efficiency lower quartile value (SSLQ), a
major surface-to-side surface grinding orientation percent
difference (MSGPD), a maximum quartile-to-median percent difference
(MQMPD), a maximum quartile difference (MQD), a major
surface-to-side surface quartile percent overlap (MSQPO), a major
surface grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD), a major surface-to-side
surface upper quartile percent difference (MSUQPD), a major
surface-to-side surface lower quartile percent difference (MSLQPD),
and a combination thereof.
[0170] In one particular embodiment, a batch of shaped abrasive
particles may include a first portion including a plurality of
shaped abrasive particles, wherein the shaped abrasive particles of
the first portion comprise a first grinding characteristic
according to the SGGT. For example, the first portion can include a
plurality of shaped abrasive particles defining one or more first
grinding characteristics according to the SGGT, such as a first
major surface grinding efficiency upper quartile value (MSUQ1), a
first major surface grinding efficiency median value (MSM1), a
first major surface grinding efficiency lower quartile value
(MSLQ1), a first side surface grinding efficiency upper quartile
value (SSUQ1), a first side surface grinding efficiency median
value (SSM1), a first side surface grinding efficiency lower
quartile value (SSLQ1), a first major surface-to-side surface
grinding orientation percent difference (MSGPD1), a first maximum
quartile-to-median percent difference (MQMPD1), a first maximum
quartile difference (MQD1), a first major surface-to-side surface
quartile percent overlap (MSQPO1), a first major surface grinding
efficiency median value and side surface grinding efficiency median
value difference (MSMD1), a first major surface-to-side surface
upper quartile percent difference (MSUQPD1), a first major
surface-to-side surface lower quartile percent difference
(MSLQPD1), and a combination thereof.
[0171] Moreover, the batch can include a second portion of abrasive
particles that can be distinct from the first portion. In
particular instances, the second portion of abrasive particles can
include a plurality of abrasive particles, which may be a plurality
of shaped abrasive particles, having one or more second grinding
characteristics significantly distinct from the first grinding
characteristics. The second grinding characteristics can include
any of the features described herein, including, but are not
limited to, a second major surface grinding efficiency upper
quartile value (MSUQ2), a second major surface grinding efficiency
median value (MSM2), a second major surface grinding efficiency
lower quartile value (MSLQ2), a second side surface grinding
efficiency upper quartile value (SSUQ2), a second side surface
grinding efficiency median value (SSM2), a second side surface
grinding efficiency lower quartile value (SSLQ2), a second major
surface-to-side surface grinding orientation percent difference
(MSGPD2), a second maximum quartile-to-median percent difference
(MQMPD2), a second maximum quartile difference (MQD2), a second
major surface-to-side surface quartile percent overlap (MSQPO2), a
second major surface grinding efficiency median value and side
surface grinding efficiency median value difference (MSMD2), a
second major surface-to-side surface upper quartile percent
difference (MSUQPD2), a second major surface-to-side surface lower
quartile percent difference (MSLQPD2), and a combination
thereof.
[0172] In certain instances, the batch including the first portion
of abrasive particles having the first grinding characteristic and
the second portion of abrasive particles having the second grinding
characteristics can have a difference between corresponding
grinding characteristics of at least about 2%. For example, the
batch may include a first portion having a particular first major
surface grinding efficiency median value (MSM1) and the second
portion can have a particular second major surface grinding
efficiency median value (MSM2), which can be distinct from the MSM1
by at least about 2%, wherein the percent difference is calculated
by the equation [(MSM1-MSM2)/MSM1].times.100%, wherein MSM1 is
greater than MSM2. If MSM2 is greater than MSM1, the equation used
is [(MSM2-MSM1)/MSM2].times.100%. In other embodiments, the
difference between the first grinding characteristic and the second
corresponding grinding characteristic can be at least about 5%,
such as at least about 8%, at least about 10%, at least about 12%,
at least about 25%, at least about 18%, at least about 20%, at
least about 22%, or even at least about 25%. It will be appreciated
that such a percent difference between any of the corresponding
grinding characteristics of the first portion and second portion
can be calculated in the same manner.
[0173] The grinding efficiency of a particular shaped abrasive
particle may be evaluated over time according to the SGGT. Notably,
the tangential force can be plotted with respect to time to provide
information on the change in grinding efficiency of the shaped
abrasive particle through the duration of the SGGT. In accordance
with one embodiment the maximum difference in force between a
maximum force and minimum force on a plot of tangential force
versus time for a shaped abrasive particle can define a grinding
efficiency time variance. It will be appreciated that the grinding
efficiency time variance can be measured for the major surface
orientation and/or the side surface orientation. FIG. 17 includes a
plot of grinding efficiency versus time for a shaped abrasive
particle according to an embodiment. Notably, in one instance, the
shaped abrasive particles of the embodiments herein can have a
major surface grinding efficiency time variance (MSTV) of not
greater than about 2 kN/mm.sup.2, as measured by the difference
between the value of the data point on the plot representing the
greatest force minus value of the data point of the plot
representing the lowest force. In other instances, the MSTV can be
not greater than about 1.8 kN/mm.sup.2, not greater than about 1.5
kN/mm.sup.2, not greater than about 1.2 kN/mm.sup.2, not greater
than about 1.1 kN/mm.sup.2, not greater than about 1 kN/mm.sup.2,
not greater than about 0.9 kN/mm.sup.2, not greater than about 0.8
kN/mm.sup.2. Still, in one non-limiting embodiment, the MSTV can be
not at least about 0.01 kN/mm.sup.2. It will be appreciated that
the shaped abrasive particles herein can have an MSTV according to
the SSGT that is within a range between any of the minimum or
maximum values noted above.
[0174] FIG. 9 includes a perspective view illustration of a portion
of an abrasive article including shaped abrasive particles having
predetermined orientation characteristics relative to a grinding
direction in accordance with an embodiment. In one embodiment, the
abrasive article can include a shaped abrasive particle 902 having
a predetermined orientation relative to another shaped abrasive
particle 903 and/or relative to a grinding direction 985. Control
of one or a combination of predetermined orientation
characteristics relative to the grinding direction 985 may
facilitate improved grinding performance of the abrasive article.
In particular, the control of the rotational orientation of the
shaped abrasive particles 902 and 903 in combination with control
of the major surface grinding efficiency and side surface grinding
efficiency can facilitate formation of fixed abrasive articles
having unique performance. It is contemplated that by understanding
and controlling the major surface grinding efficiency and side
surface grinding efficiency of shaped abrasive particles, and
further by controlling the orientation of the shaped abrasive
particles relative to the backing 901 and a grinding direction 985,
the fixed abrasive article may be more properly tailored to various
applications.
[0175] The grinding direction 985 may be an intended direction of
movement of the abrasive article relative to a workpiece in a
material removal operation. In particular instances, the grinding
direction 985 may be related to the dimensions of the backing 901.
For example, in one embodiment, the grinding direction 985 may be
substantially perpendicular to the lateral axis 981 of the backing
and substantially parallel to the longitudinal axis 980 of the
backing 901. The predetermined orientation characteristics of the
shaped abrasive particle 902 may define an initial contact surface
of the shaped abrasive particle 902 with a workpiece. For example,
the shaped abrasive particle 902 can have a major surfaces 963 and
964, and side surfaces 965 and 966 extending between the major
surfaces 963 and 964. The predetermined orientation characteristics
of the shaped abrasive particle 902 can position the particle such
that the major surface 963 is configured to make initial contact
with a workpiece before the other surfaces of the shaped abrasive
particle 902. Such an orientation may be considered a major surface
orientation relative to the grinding direction 985. More
particularly, the shaped abrasive particle 902 can have a bisecting
axis 931 having a particular orientation relative to the grinding
direction. For example, as illustrated, the vector of the grinding
direction 985 and the bisecting axis 931 are substantially
perpendicular to each other. It will be appreciated that just as
any range of predetermined rotational orientations are contemplated
for a shaped abrasive particle, any range of orientations of the
shaped abrasive particles relative to the grinding direction 985
are contemplated and can be utilized. Such an orientation as shown
for the shaped abrasive particle 902 may be particularly suitable
for shaped abrasive particles having a major surface grinding
efficiency that is better than a side surface grinding efficiency.
It will be appreciated that for such particles, a coated abrasive
article may include a significant portion of the shaped abrasive
particles in a major surface orientation relative to the grinding
direction 985.
[0176] The shaped abrasive particle 903 can have different
predetermined orientation characteristics relative to the shaped
abrasive particle 902 and the grinding direction 985. As
illustrated, the shaped abrasive particle 903 can include major
surfaces 991 and 992, which can be joined by side surfaces 971 and
972. Moreover, as illustrated, the shaped abrasive particle 903 can
have a bisecting axis 973 forming a particular angle relative to
the vector of the grinding direction 985. As illustrated, the
bisecting axis 973 of the shaped abrasive particle 903 can have a
substantially parallel orientation with the grinding direction 985
such that the angle between the bisecting axis 973 and the grinding
direction 985 is essentially 0 degrees. Accordingly, the
predetermined orientation characteristics of the shaped abrasive
particle facilitate initial contact of the side surface 972 with a
workpiece before any of the other surfaces of the shaped abrasive
particle. Such an orientation of the shaped abrasive particle 903
may be considered a side surface orientation relative to the
grinding direction 985. Such an orientation as illustrated for the
shaped abrasive particle 903 may be particularly suitable for
shaped abrasive particles having a side surface grinding efficiency
that is better than a major surface grinding efficiency. It will be
appreciated that for such particles, a coated abrasive article may
include a significant portion of the shaped abrasive particles in a
side surface orientation relative to the grinding direction
985.
[0177] It will be appreciated that the abrasive article can include
one or more groups of shaped abrasive particles that can be
arranged in a predetermined distribution relative to each other,
and more particularly can have distinct predetermined orientation
characteristics that define groups of shaped abrasive particles.
The groups of shaped abrasive particles, as described herein, can
have a predetermined orientation relative to a grinding direction.
Moreover, the abrasive articles herein can have one or more groups
of shaped abrasive particles, each of the groups having a different
predetermined orientation relative to a grinding direction.
Utilization of groups of shaped abrasive particles having different
predetermined orientations relative to a grinding direction can
facilitate improved performance of the abrasive article.
Example 1
[0178] Five samples of shaped abrasive particles were analyzed
using SGGT. A first sample, Sample S1, includes shaped abrasive
particles made from a seeded sol-gel, having an average major
surface radius of curvature of approximately 300 microns, an
average side corner radius of curvature of approximately 30
microns, a ratio of SSCR/MSCR of approximately 0.075, a height of
approximately 400 microns, and a flashing percentage of
approximately 4%. FIG. 10 includes an image of a representative
shaped abrasive particle from Sample S1.
[0179] A second sample, Sample S2, includes shaped abrasive
particles having a rare-earth element doped alpha-alumina
composition, an average major surface radius of curvature of
approximately 300 microns, an average side corner radius of
curvature of approximately 30 microns, a ratio of SSCR/MSCR of
approximately 0.075, a height of approximately 400 microns, a
flashing percentage of approximately 4%. FIG. 11 includes an image
of a representative shaped abrasive particle from Sample S2.
[0180] A third sample, Sample S3, includes shaped abrasive
particles made from a seeded sol-gel, having an average major
surface radius of curvature of approximately 500 microns, an
average side corner radius of curvature of approximately 30
microns, a ratio of SSCR/MSCR of approximately 0.06, a height of
approximately 500 microns, and a flashing percentage of
approximately 16%. FIG. 12 includes an image of a representative
shaped abrasive particle from Sample S3.
[0181] A fourth sample, Sample S4, includes shaped abrasive
particles having a rare-earth element doped alpha-alumina
composition, an average major surface radius of curvature of
approximately 500 microns, an average side corner radius of
curvature of approximately 30 microns, a ratio of SSCR/MSCR of
approximately 0.06, a height of approximately 500 microns, and a
flashing percentage of approximately 17%. FIG. 13 includes an image
of a representative shaped abrasive particle from Sample S4.
[0182] A conventional sample, Sample CS1, is a sample of Cubitron
II shaped abrasive particles commercially available as 3M984F from
3M Corporation. The shaped abrasive particles of Sample CS1 had a
rare-earth element doped alpha-alumina composition, an average
major surface radius of curvature of approximately 30 microns, an
average side corner radius of curvature of approximately 30
microns, a ratio of SSCR/MSCR of approximately 1, a height of
approximately 260 microns, and a flashing percentage of
approximately 4%. FIG. 14 includes an image of a representative
shaped abrasive particle from Sample CS1.
[0183] All samples were tested according to the SGGT in a major
surface orientation and side orientation. The results of the data
are provided in FIG. 15, which includes a plot of major surface
grinding efficiency and side surface grinding efficiency for each
of the samples. Sample CS1 had a MSGPD of 37, a MQD of about 6, a
MSQPO of 12, a MSMD of 1.7, a MQMPD of 47, a MSUQPD of 54, a MSLQPD
of 27, and a MSTV of 2.8.
[0184] By contrast, Sample S1 had a MSGPD of 57, a MQD of 23, a
MSQPO of about 12, a MSMD of 6.6, a MQMPD of 57, a MSUQPD of 65,
and a MSLQPD of 58. Sample S2 had a MSGPD of 47, a MQD of 8, a
MSQPO of about 28, a MSMD of 2.7, and a MQMPD of 50, a MSUQPD of
39, and a MSLQPD of 56. Sample S3 had a MSGPD of 61, a MQD of 17, a
MSQPO of about 0.3, a MSMD of 3.9, and a MQMPD of 66, a MSUQPD of
79, a MSLQPD of 47, and a MSTV of 0.7. Sample S4 had a MSGPD of 53,
a MQD of 7, a MSQPO of about 0.2, a MSMD of 2.7, and a MQMPD of 38,
a MSUQPD of 58, a MSLQPD of 48, and a MSTV of 1.4.
[0185] Furthermore, by comparison, each of Samples S1-S4 had a
major surface grinding efficiency that was equal to or better than
that of Sample CS1. In particular, the MSM values of Samples S3 and
S4 were nearly twice as good as compared to the MSM value of Sample
CS1 (i.e., half of the force per area median value). Moreover, each
of the Samples S1-S4 had SSM values that were significantly greater
than the corresponding MSM values. Samples S1-S4 had SSM values
that were approximately twice as great as the corresponding MSM
values. By contrast, Sample CS1 had a SSM value less than the MSM
value, and more particularly, about 40% less than the MSM
value.
[0186] The present application represents a departure from the
state of the art. The shaped abrasive particles and fixed abrasive
articles of the embodiments herein include a particular combination
of features distinct from other articles. For example, the
particles demonstrate remarkable and unexpected performance in
terms of MSUQ, MSM, MSLQ, SSUQ, SSM, SSLQ, MSGPD, MQMPD, MQD,
MSQPO, MSMD, MSUQPD, MSLQPD, MSTV, and a combination thereof.
Moreover, while not completely understood and not wishing to be
tied to a particular theory, it is thought that one or a
combination of features of the embodiments herein facilitate the
performance of the shaped abrasive particles, including but not
limited to, aspect ratio, composition, additives, two-dimensional
shape, three-dimensional shape, difference in height, difference in
height profile, flashing percentage, height, dishing, major surface
corner radius of curvature, side surface corner radius of
curvature, SSCR/MSCR ratio, relative side of a planar portion, and
a combination thereof.
[0187] As used herein, the terms "comprises," "comprising,"
"includes," "including," "has," "having," or any other variation
thereof, are intended to cover a non-exclusive inclusion. For
example, a process, method, article, or apparatus that comprises a
list of features is not necessarily limited only to those features
but can include other features not expressly listed or inherent to
such process, method, article, or apparatus. Further, unless
expressly stated to the contrary, "or" refers to an inclusive-or
and not to an exclusive-or. For example, a condition A or B is
satisfied by any one of the following: A is true (or present) and B
is false (or not present), A is false (or not present) and B is
true (or present), and both A and B are true (or present).
[0188] The use of "a" or "an" is employed to describe elements and
components described herein. This is done merely for convenience
and to give a general sense of the scope of the invention. This
description should be read to include one or at least one and the
singular also includes the plural, or vice versa, unless it is
clear that it is meant otherwise.
[0189] The above-disclosed subject matter is to be considered
illustrative, and not restrictive, and the appended claims are
intended to cover all such modifications, enhancements, and other
embodiments, which fall within the true scope of the present
invention. Thus, to the maximum extent allowed by law, the scope of
the present invention is to be determined by the broadest
permissible interpretation of the following claims and their
equivalents, and shall not be restricted or limited by the
foregoing detailed description.
[0190] The Abstract of the Disclosure is provided to comply with
Patent Law and is submitted with the understanding that it will not
be used to interpret or limit the scope or meaning of the claims.
In addition, in the foregoing Detailed Description of the Drawings,
various features may be grouped together or described in a single
embodiment for the purpose of streamlining the disclosure. This
disclosure is not to be interpreted as reflecting an intention that
the claimed embodiments require more features than are expressly
recited in each claim. Rather, as the following claims reflect,
inventive subject matter may be directed to less than all features
of any of the disclosed embodiments. Thus, the following claims are
incorporated into the Detailed Description of the Drawings, with
each claim standing on its own as defining separately claimed
subject matter.
[0191] Items
[0192] Item 1. A shaped abrasive particle comprising a major
surface-to-side surface grinding orientation percent difference
(MSGPD) of at least about 40%.
[0193] Item 2. A shaped abrasive particle comprising a maximum
quartile-to-median percent difference (MQMPD) of at least about
48%.
[0194] Item 3. A batch of abrasive particles comprising a first
portion including a plurality of shaped abrasive particles having a
major surface-to-side surface grinding orientation percent
difference (MSGPD) of at least about 40%.
[0195] Item 4. A batch of abrasive particles comprising a first
portion including a plurality of shaped abrasive particles having a
maximum quartile-to-median percent difference (MQMPD) of at least
about 48%.
[0196] Item 5. A shaped abrasive particle comprising a major
surface grinding efficiency median value (MSM) of not greater than
about 4 kN/mm2.
[0197] Item 6. The shaped abrasive particle or batch of abrasive
particles of any of items 1 and 3, wherein the shaped abrasive
particle comprises a maximum quartile-to-median percent difference
(MQMPD) of at least about 48%.
[0198] Item 7. The shaped abrasive particle or batch of abrasive
particles of any one of items 2, 4, 5, and 6, wherein the MQMPD is
at least about 49%, at least about 50%, at least about 52%, at
least about 54%, at least about 56%, at least about 58%.
[0199] Item 8. The shaped abrasive particle or batch of abrasive
particles of any one of items 2, 4, 5 and 6, wherein the MQMPD is
not greater than about 99%.
[0200] Item 9. The shaped abrasive particle or batch of abrasive
particles of any one of items 2 and 6, wherein the shaped abrasive
particle comprises a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%.
[0201] Item 10. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 3, 5, and 9, wherein the shaped
abrasive particle comprises a major surface-to-side surface
grinding orientation percent difference (MSGPD) of at least about
42%, at least about 44%, at least about 46%, at least about 48%, at
least about 50%, at least about 52%, at least about 54%, at least
about 55%, at least about 56%, at least about 57%, at least about
58%, at least about 59%.
[0202] Item 11. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 3, 5, and 9, wherein the shaped
abrasive particle comprises a major surface-to-side surface
grinding orientation percent difference (MSGPD) of not greater than
about 99%.
[0203] Item 12. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 2, 3, 4, and 5, wherein the shaped
abrasive particle comprises a body having a length (l), a width
(w), and a height (h), wherein the width>length, the
length>height, and the width>height.
[0204] Item 13. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 2, 3, 4, and 5, wherein the shaped
abrasive particle comprises a body having a first major surface, a
second major surface, and at least one side surface extending
between the first major surface and the second major surface.
[0205] Item 14. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a major surface corner radius of curvature of at least about 100
microns, at least about 120 microns, at least about 140 microns, at
least about 160 microns, 180 microns, at least about 190 microns,
at least about 200 microns, at least about 210 microns, at least
about 220 microns, at least about 230 microns at least about 240
microns, at least about 250 microns, at least about 260 microns at
least about 270 microns, at least about 280 microns, at least about
290 microns.
[0206] Item 15. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a major surface corner radius of curvature of at not greater than
about 800 microns, not greater than about 700 microns, not greater
than about 600 microns, not greater than about 500 microns, not
greater than about 400 microns.
[0207] Item 16. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a side surface corner radius of curvature of not greater than about
800 microns, such as not greater than about 700 microns, not
greater than about 600 microns, not greater than about 500 microns,
not greater than about 400 microns, not greater than about 300
microns, not greater than about 200 microns, not greater than about
280 microns, not greater than about 260 microns, not greater than
about 240 microns, not greater than about 220 microns, not greater
than about 200 microns, not greater than about 180 microns, not
greater than about 160 microns, not greater than about 140 microns,
not greater than about 100 microns, not greater than about 80
microns, or even not greater than about 60 microns.
[0208] Item 17. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a side surface corner radius of curvature of at least about 1
micron.
[0209] Item 18. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a ratio (SSCR/MSCR) of a side surface corner radius of curvature
(SSCR) to a major surface corner radius of curvature (MSCR) of not
greater than about 1, not greater than about 0.9, not greater than
about 0.8, not greater than about 0.7, not greater than about 0.6,
not greater than about 0.5, not greater than about 0.4, not greater
than about 0.2, not greater than about 0.1, not greater than about
0.09.
[0210] Item 19. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a ratio (SSCR/MSCR) of a side surface corner radius of curvature
(SSCR) to a major surface corner radius of curvature (MSCR) of at
least about 0.001, at least about 0.005, at least about 0.01
[0211] Item 20. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a major surface corner radius of curvature greater than a side
surface corner radius of curvature.
[0212] Item 21. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the height (h) is
at least about 20% of the width (w), at least about 25%, at least
about 30%, at least about 33%, and not greater than about 80%, not
greater than about 76%, not greater than about 73%, not greater
than about 70%, not greater than about 68% of the width, not
greater than about 56% of the width, not greater than about 48% of
the width, not greater than about 40% of the width.
[0213] Item 22. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the height (h) is
at least about 400 microns, at least about 450 microns, at least
about 475 microns, at least about 500 microns, and not greater than
about 3 mm, not greater than about 2 mm, not greater than about 1.5
mm, not greater than about 1 mm, not greater than about 800
microns.
[0214] Item 23. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the width is at
least about 600 microns, at least about 700 microns, at least about
800 microns, at least about 900 microns, and not greater than about
4 mm, not greater than about 3 mm, not greater than about 2.5 mm,
not greater than about 2 mm.
[0215] Item 24. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a percent flashing of not greater than about 20%, not greater than
about 18%, not greater than about 15%, not greater than about 12%,
not greater than about 10%, not greater than about 8%, not greater
than about 6%, not greater than about 4%, and at least about
1%.
[0216] Item 25. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a dishing value (d) of not greater than about 2, not greater than
about 1.9, not greater than about 1.8, not greater than about 1.7,
not greater than about 1.6, not greater than about 1.5, not greater
than about 1.2, and at least about 0.9, at least about 1.0.
[0217] Item 26. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a primary aspect ratio of width:length of at least about 1:1 and
not greater than about 10:1.
[0218] Item 27. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a secondary aspect ratio defined by a ratio of width:height within
a range between about 5:1 and about 1:1.
[0219] Item 28. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a tertiary aspect ratio defined by a ratio of length:height within
a range between about 6:1 and about 1.5:1.
[0220] Item 29. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a two-dimensional polygonal shape as viewed in a plane defined by a
length and width, wherein the body comprises a shape selected from
the group consisting of triangular, quadrilateral, rectangular,
trapezoidal, pentagonal, hexagonal, heptagonal, octagonal, and a
combination thereof, wherein the body comprises a two-dimensional
shape as viewed in a plane defined by a length and a width of the
body selected from the group consisting of ellipsoids, Greek
alphabet characters, Latin alphabet characters, Russian alphabet
characters, triangles, and a combination thereof.
[0221] Item 30. The shaped abrasive particle or batch of abrasive
particles of item 13, wherein the first major surface defines an
area different than the second major surface, wherein the first
major surface defines an area greater than an area defined by the
second major surface, wherein the first major surface defines an
area less than an area defined by the second major surface.
[0222] Item 31. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body is
essentially free of a binder, wherein the body is essentially free
of an organic material.
[0223] Item 32. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a polycrystalline material, wherein the polycrystalline material
comprises grains, wherein the grains are selected from the group of
materials consisting of nitrides, oxides, carbides, borides,
oxynitrides, diamond, and a combination thereof, wherein the grains
comprise an oxide selected from the group of oxides consisting of
aluminum oxide, zirconium oxide, titanium oxide, yttrium oxide,
chromium oxide, strontium oxide, silicon oxide, and a combination
thereof, wherein the grains comprise alumina, wherein the grains
consist essentially of alumina.
[0224] Item 33. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body is formed
from a seeded sol gel.
[0225] Item 34. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
a polycrystalline material having an average grain size not greater
than about 1 micron.
[0226] Item 35. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body is a
composite comprising at least about 2 different types of abrasive
grains.
[0227] Item 36. The shaped abrasive particle or batch of abrasive
particles of any one of items 12 and 13, wherein the body comprises
an additive, wherein the additive comprises an oxide, wherein the
additive comprises a metal element, wherein the additive comprises
a rare-earth element.
[0228] Item 37. The shaped abrasive particle or batch of abrasive
particles of item 36, wherein the additive comprises a dopant
material, wherein the dopant material includes an element selected
from the group consisting of an alkali element, an alkaline earth
element, a rare earth element, a transition metal element, and a
combination thereof, wherein the dopant material comprises an
element selected from the group consisting of hafnium, zirconium,
niobium, tantalum, molybdenum, vanadium, lithium, sodium,
potassium, magnesium, calcium, strontium, barium, scandium,
yttrium, lanthanum, cesium, praseodymium, chromium, cobalt, iron,
germanium, manganese, nickel, titanium, zinc, and a combination
thereof.
[0229] Item 38. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 2, 3, and 4, further comprising a
major surface grinding efficiency and a side surface grinding
efficiency, wherein the major surface grinding efficiency is less
than the side surface grinding efficiency.
[0230] Item 39. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 2, 3, and 4, further comprising a
major surface grinding efficiency and a side surface grinding
efficiency, wherein the major surface grinding efficiency is
greater than the side surface grinding efficiency.
[0231] Item 40. The shaped abrasive particle or batch of abrasive
particles of any one of items 1, 2, 3, and 4, further comprising a
major surface grinding efficiency upper quartile value (MSUQ), a
major surface grinding efficiency median value (MSM), a major
surface grinding efficiency lower quartile value (MSLQ), a side
surface grinding efficiency upper quartile value (SSUQ), a side
surface grinding efficiency median value (SSM), a side surface
grinding efficiency lower quartile (SSLQ), and a major surface
grinding efficiency time variance (MSTV).
[0232] Item 41. The shaped abrasive particle item 5, further
comprising a major surface grinding efficiency upper quartile value
(MSUQ), a major surface grinding efficiency lower quartile value
(MSLQ), a side surface grinding efficiency upper quartile value
(SSUQ), a side surface grinding efficiency median value (SSM), and
a side surface grinding efficiency lower quartile (SSLQ).
[0233] Item 42. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, further comprising a
maximum quartile difference (MQD) of at least about 6 kN/mm2, at
least about 6.2 kN/mm2, at least about 6.5 kN/mm2, at least about
6.8 kN/mm2, at least about 7 kN/mm2, at least about 7.5 kN/mm2, at
least about 8 kN/mm2, at least about 9 kN/mm2, at least about 10
kN/mm2, at least about 12 kN/mm2.
[0234] Item 43. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, further comprising a major
surface-to-side surface quartile percent overlap (MSQPO) of not
greater than about 11%, not greater than about 10%, not greater
than about 9%, not greater than about 8%, not greater than about
7%, not greater than about 6%, not greater than about 5%, not
greater than about 4%, not greater than about 3%, not greater than
about 2%, not greater than about 1%.
[0235] Item 44. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, further comprising a major
surface grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD) of at least about 1.9
kN/mm2, at least about 2 kN/mm2, at least about 2.3 kN/mm2, at
least about 2.5 kN/mm2, at least about 2.7 kN/mm2, at least about 3
kN/mm2, at least about 3.5 kN/mm2, at least about 4 kN/mm2, at
least about 4.5 kN/mm2, at least about 5 kN/mm2, at least about 6
kN/mm2.
[0236] Item 45. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, further comprising a major
surface-to-side surface upper quartile percent difference (MSUQPD)
of at least about 54%, at least about 55%, at least about 56%, at
least about 57%, at least about 58%, at least about 60%, at least
about 63%, at least about 65%, at least about 70%.
[0237] Item 46. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, further comprising a major
surface-to-side surface lower quartile percent difference (MSLQPD)
of at least about 28%, at least about 30%, at least about 32%, at
least about 35%, at least about 37%, at least about 40%, at least
about 42%, at least about 45%, at least about 47% at least about
50%, at least about 52%, at least about 55%, at least about
57%.
[0238] Item 47. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the major surface
grinding efficiency upper quartile value (MSUQ) is not greater than
about 8.3 kN/mm2, not greater than about 8 kN/mm2, not greater than
about 7.8 kN/mm2, not greater than about 7.5 kN/mm2, not greater
than about 7.2 kN/mm2, not greater than about 7 kN/mm2, not greater
than about 6.8 kN/mm2, not greater than about 6.5 kN/mm2, not
greater than about 6.2 kN/mm2, not greater than about 6 kN/mm2, not
greater than about 5.5 kN/mm2, not greater than about 5.2 kN/mm2,
not greater than about 4 kN/mm2.
[0239] Item 48. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the major surface
grinding efficiency time variance (MSTV) is not greater than about
2 kN/mm2, not greater than about 1.8 kN/mm2, not greater than about
1.5 kN/mm2, not greater than about 1.2 kN/mm2, not greater than
about 1.1 kN/mm2, not greater than about 1 kN/mm2, not greater than
about 0.9 kN/mm2, not greater than about 0.8 kN/mm2.
[0240] Item 49. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the major surface
grinding efficiency upper quartile value (MSUQ) is at least about
0.1 kN/mm2.
[0241] Item 50. The shaped abrasive particle or batch of abrasive
particles of item 40, wherein the major surface grinding efficiency
median value (MSM) is less than the major surface grinding
efficiency upper quartile value (MSUQ), wherein the major surface
grinding efficiency median value (MSM) is not greater than about 8
kN/mm2, not greater than about 7.8 kN/mm2, not greater than about
7.5 kN/mm2, not greater than about 7.2 kN/mm2, not greater than
about 7 kN/mm2, not greater than about 6.8 kN/mm2, not greater than
about 6.5 kN/mm2, not greater than about 6.2 kN/mm2, not greater
than about 6 kN/mm2, not greater than about 5.8 kN/mm2, not greater
than about 5.5 kN/mm2, not greater than about 5.2 kN/mm2, not
greater than about 5 kN/mm2, not greater than about 4.8 kN/mm2, not
greater than about 4.6 kN/mm2, not greater than about 4.2 kN/mm2,
not greater than about 4 kN/mm2.
[0242] Item 51. The shaped abrasive particle or batch of abrasive
particles of any one of items 5 and 50, wherein the major surface
grinding efficiency median value (MSM) is not greater than about
3.8 kN/mm2, not greater than about 3.6 kN/mm2, not greater than
about 3.2 kN/mm2, not greater than about 3 kN/mm2, not greater than
about 2.8 kN/mm2, not greater than about 2.6 kN/mm2.
[0243] Item 52. The shaped abrasive particle or batch of abrasive
particles of any one of items 5 and 50, wherein the major surface
grinding efficiency median value (MSM) is at least about 0.1
kN/mm2.
[0244] Item 53. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the major surface
grinding efficiency lower quartile value (MSLQ) is less than the
major surface grinding efficiency median value (MSM), wherein the
major surface grinding efficiency lower quartile value (MSLQ) is
not greater than about 8 kN/mm2, not greater than about 7 kN/mm2,
not greater than about 6 kN/mm2, not greater than about 5 kN/mm2,
not greater than about 4 kN/mm2, not greater than about kN/mm2, not
greater than about 6.5 kN/mm2, not greater than about 6.2 kN/mm2,
not greater than about 6 kN/mm2, not greater than about 5.8 kN/mm2,
not greater than about 5.5 kN/mm2, not greater than about 5.2
kN/mm2, not greater than about 5 kN/mm2, not greater than about 4.8
kN/mm2, not greater than about 4.6 kN/mm2, not greater than about
4.2 kN/mm2, not greater than about 4 kN/mm2, not greater than about
3.8 kN/mm2, not greater than about 3.6 kN/mm2, not greater than
about 3.2 kN/mm2, not greater than about 3 kN/mm2, not greater than
about 2.8 kN/mm2, not greater than about 2.6 kN/mm2, not greater
than about 2.2 kN/mm2, not greater than about 2 kN/mm2, not greater
than about 1.9 kN/mm2.
[0245] Item 54. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the major surface
grinding efficiency lower quartile value (MSLQ) is at least about
0.1 kN/mm2.
[0246] Item 55. The shaped abrasive particle or batch of abrasive
particles of item 40, wherein the side surface grinding efficiency
upper quartile value (SSUQ) is at least about 4.5 kN/mm2, at least
about 5 kN/mm2, at least about 5.5 kN/mm2, at least about 6 kN/mm2,
at least about 6.5 kN/mm2, at least about 7 kN/mm2, at least about
7.5 kN/mm2, at least about 8 kN/mm2, at least about 8.5 kN/mm2, at
least about 9 kN/mm2, at least about 10 kN/mm2, at least about 15
kN/mm2, at least about 20 kN/mm2, at least about 25 kN/mm2.
[0247] Item 56. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the side surface
grinding efficiency upper quartile value (SSUQ) is not greater than
about 100 kN/mm2.
[0248] Item 57. The shaped abrasive particle or batch of abrasive
particles of item 40, wherein the side surface grinding efficiency
median value (SSM) is less than the side surface grinding
efficiency upper quartile value (SSUQ), wherein the side surface
grinding efficiency median value (SSM) is at least about 3 kN/mm2,
at least about 3.2 kN/mm2, at least about 3.5 kN/mm2, at least
about 3.7 kN/mm2, at least about 4 kN/mm2, at least about 4.2
kN/mm2, at least about 4.5 kN/mm2, at least about 4.7 kN/mm2, at
least about 5 kN/mm2, at least about 5.2 kN/mm2, at least about 5.5
kN/mm2, at least about 5.7 kN/mm2, at least about 6 kN/mm2, at
least about 6.2 kN/mm2, at least about 6.5 kN/mm2, at least about 7
kN/mm2, at least about 8 kN/mm2, at least about 9 kN/mm2, at least
about 10 kN/mm2.
[0249] Item 58. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the side surface
grinding efficiency median value (SSM) is not greater than about
100 kN/mm2.
[0250] Item 59. The shaped abrasive particle or batch of abrasive
particles of item 40, wherein the side surface grinding efficiency
lower quartile value (SSLQ) is less than the side surface grinding
efficiency median value (SSM), wherein the side surface grinding
efficiency lower quartile value (SSLQ) is at least about 2.5
kN/mm2, at least about 2.7 kN/mm2, at least about 3 kN/mm2, at
least about 3.1 kN/mm2, at least about 3.3 kN/mm2, at least about
3.5 kN/mm2, at least about 3.6 kN/mm2, at least about 3.8 kN/mm2,
at least about 4 kN/mm2, at least about 5 kN/mm2, at least about 6
kN/mm2.
[0251] Item 60. The shaped abrasive particle or batch of abrasive
particles of any one of items 40 and 41, wherein the side surface
grinding efficiency lower quartile value (SSLQ) is not greater than
about 100 kN/mm2.
[0252] Item 61. The batch of abrasive particles of any one of items
3 and 4, wherein the first portion comprises a majority of a total
number of shaped abrasive particles of the batch.
[0253] Item 62. The batch of abrasive particles of any one of items
3 and 4, wherein the first portion comprises a minority of a total
number of shaped abrasive particles of the batch.
[0254] Item 63. The batch of abrasive particles of any one of items
3 and 4, wherein the first portion defines at least 1% of a total
number of shaped abrasive particles of the batch.
[0255] Item 64. The batch of abrasive particles of any one of items
3 and 4, wherein the first portion defines not greater than about
99% of a total number of shaped abrasive particles of the
batch.
[0256] Item 65. The batch of abrasive particles of any one of items
3 and 4, wherein the batch further comprises a second portion of
shaped abrasive particles, wherein the second portion of shaped
abrasive particles have a second grinding efficiency characteristic
different than a first grinding efficiency characteristic of the
first portion, wherein the second grinding efficiency
characteristic is selected from the group consisting of: a major
surface grinding efficiency upper quartile value (MSUQ); a major
surface grinding efficiency median value (MSM); a major surface
grinding efficiency lower quartile value (MSLQ); a side surface
grinding efficiency upper quartile value (SSUQ); a side surface
grinding efficiency median value (SSM); a side surface grinding
efficiency lower quartile value (SSLQ); a major surface-to-side
surface grinding orientation percent difference (MSGPD); a maximum
quartile-to-median percent difference (MQMPD); a maximum quartile
difference (MQD); a major surface-to-side surface quartile percent
overlap (MSQPO); a major surface grinding efficiency median value
and side surface grinding efficiency median value difference
(MSMD); a major surface-to-side surface upper quartile percent
difference (MSUQPD); a major surface-to-side surface lower quartile
percent difference (MSLQPD); a major surface grinding efficiency
time variance (MSTV); and a combination thereof.
[0257] Item 66. The batch of abrasive particles of any one of items
3 and 4, wherein the batch of abrasive particles are part of a
fixed abrasive article, wherein the fixed abrasive article is
selected from the group consisting of bonded abrasive articles,
coated abrasive articles, and a combination thereof.
[0258] Item 67. The batch of abrasive particles of any one of items
3 and 4, wherein the batch of abrasive particles are part of a
fixed abrasive article, wherein the fixed abrasive article
comprises a coated abrasive article, and wherein the first portion
of the batch includes a plurality of shaped abrasive particles,
each of the shaped abrasive particles of the plurality of shaped
abrasive particles are arranged in a controlled orientation
relative to a backing, the controlled orientation including at
least one of a predetermined rotational orientation, a
predetermined lateral orientation, and a predetermined longitudinal
orientation.
[0259] Item 68. The batch of abrasive particles of any one of items
3 and 4, wherein a majority of the first portion of shaped abrasive
particles are coupled to a backing in a side orientation, wherein
at least about 55% of the shaped abrasive particles of the first
portion are coupled to the backing in a side orientation, at least
about 60%, at least about 65%, at least about 70%, at least about
75%, at least about 77%, at least about 80%, at least about 82%,
and not greater than about 99%.
[0260] Item 69. The batch of abrasive particles of any one of items
3 and 4, wherein the plurality of shaped abrasive particles of the
first portion define an open coat, wherein the plurality of shaped
abrasive particles of the first portion define a closed coat,
wherein the open coat comprises a coating density of not greater
than about 70 particles/cm2.
[0261] Item 70. The batch of abrasive particles of any one of items
3 and 4, wherein the batch of abrasive particles are part of a
coated abrasive article, wherein the first portion including the
plurality of shaped abrasive particles overlies a backing, wherein
the backing comprises a woven material, wherein the backing
comprises a non-woven material, wherein the backing comprises an
organic material, wherein the backing comprises a polymer, wherein
the backing comprises a material selected from the group consisting
of cloth, paper, film, fabric, fleeced fabric, vulcanized fiber,
woven material, non-woven material, webbing, polymer, resin,
phenolic resin, phenolic-latex resin, epoxy resin, polyester resin,
urea formaldehyde resin, polyester, polyurethane, polypropylene,
polyimides, and a combination thereof.
[0262] Item 71. The batch of abrasive particles of item 70, wherein
the backing comprises an additive chosen from the group consisting
of catalysts, coupling agents, curants, anti-static agents,
suspending agents, anti-loading agents, lubricants, wetting agents,
dyes, fillers, viscosity modifiers, dispersants, defoamers, and
grinding agents.
[0263] Item 72. The batch of abrasive particles of item 70, further
comprising an adhesive layer overlying the backing, wherein the
adhesive layer comprises a make coat, wherein the make coat
overlies the backing, wherein the make coat is bonded directly to a
portion of the backing, wherein the make coat comprises an organic
material, wherein the make coat comprises a polymeric material,
wherein the make coat comprises a material selected from the group
consisting of polyesters, epoxy resins, polyurethanes, polyamides,
polyacrylates, polymethacrylates, poly vinyl chlorides,
polyethylene, polysiloxane, silicones, cellulose acetates,
nitrocellulose, natural rubber, starch, shellac, and a combination
thereof.
[0264] Item 73. The batch of abrasive particles of item 72, wherein
the adhesive layer comprises a size coat, wherein the size coat
overlies a portion of the plurality of shaped abrasive particles,
wherein the size coat overlies a make coat, wherein the size coat
is bonded directly to a portion of the first abrasive particle,
wherein the size coat comprises an organic material, wherein the
size coat comprises a polymeric material, wherein the size coat
comprises a material selected from the group consisting of
polyesters, epoxy resins, polyurethanes, polyamides, polyacrylates,
polymethacrylates, poly vinyl chlorides, polyethylene,
polysiloxane, silicones, cellulose acetates, nitrocellulose,
natural rubber, starch, shellac, and a combination thereof.
[0265] Item 74. An abrasive article comprising: a backing: a batch
of abrasive particles comprising a first portion including a
plurality of shaped abrasive particles overlying the backing,
wherein the plurality of shaped abrasive particles of the first
portion comprise at least one first grinding efficiency
characteristic of: a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%; a
maximum quartile-to-median percent difference (MQMPD) of at least
about 48% a major surface grinding efficiency median value (MSM) of
not greater than about 4 kN/mm2; and a combination thereof.
[0266] Item 75. The abrasive article of item 74, wherein a majority
of the plurality of shaped abrasive particles of the first portion
of the batch are arranged in a side orientation relative to the
backing.
[0267] Item 76. The abrasive article of item 74, wherein a majority
of the plurality of shaped abrasive particles of the first portion
of the batch comprise a substantially random rotational orientation
relative to the backing.
[0268] Item 77. The abrasive article of item 74, wherein a majority
of the plurality of shaped abrasive particles of the first portion
of the batch comprise a substantially random rotational orientation
relative to a predetermined grinding direction.
[0269] Item 78. The abrasive article of item 74, wherein at least
about 55% of the plurality of shaped abrasive particles of the
first portion are oriented in a side orientation, at least about
60%, at least about 65%, at least about 70%, at least about 75%, at
least about 77%, at least about 80%, at least about 82%, and not
greater than about 99%.
[0270] Item 79. The abrasive article of item 74, wherein the
plurality of shaped abrasive particles of the first portion define
an open coat, wherein the plurality of shaped abrasive particles of
the first portion define a closed coat, wherein the open coat
comprises a coating density of not greater than about 70
particles/cm2, not greater than about 65 particles/cm2, not greater
than about 60 particles/cm2, not greater than about 55
particles/cm2, not greater than about 50 particles/cm2, at least
about 5 particles/cm2, at least about 10 particles/cm2.
[0271] Item 80. The abrasive article of item 74, wherein the
backing comprises a woven material, wherein the backing comprises a
non-woven material, wherein the backing comprises an organic
material, wherein the backing comprises a polymer, wherein the
backing comprises a material selected from the group consisting of
cloth, paper, film, fabric, fleeced fabric, vulcanized fiber, woven
material, non-woven material, webbing, polymer, resin, phenolic
resin, phenolic-latex resin, epoxy resin, polyester resin, urea
formaldehyde resin, polyester, polyurethane, polypropylene,
polyimides, and a combination thereof.
[0272] Item 81. The abrasive article of item 74, wherein the
backing comprises an additive chosen from the group consisting of
catalysts, coupling agents, curants, anti-static agents, suspending
agents, anti-loading agents, lubricants, wetting agents, dyes,
fillers, viscosity modifiers, dispersants, defoamers, and grinding
agents.
[0273] Item 82. The abrasive article of item 74, wherein further
comprising an adhesive layer overlying the backing, wherein the
adhesive layer comprises a make coat, wherein the make coat
overlies the backing, wherein the make coat is bonded directly to a
portion of the backing, wherein the make coat comprises an organic
material, wherein the make coat comprises a polymeric material,
wherein the make coat comprises a material selected from the group
consisting of polyesters, epoxy resins, polyurethanes, polyamides,
polyacrylates, polymethacrylates, poly vinyl chlorides,
polyethylene, polysiloxane, silicones, cellulose acetates,
nitrocellulose, natural rubber, starch, shellac, and a combination
thereof.
[0274] Item 83. The abrasive article of item 82, wherein the
adhesive layer comprises a size coat, wherein the size coat
overlies a portion of the plurality of shaped abrasive particles,
wherein the size coat overlies a make coat, wherein the size coat
is bonded directly to a portion of the first abrasive particle,
wherein the size coat comprises an organic material, wherein the
size coat comprises a polymeric material, wherein the size coat
comprises a material selected from the group consisting of
polyesters, epoxy resins, polyurethanes, polyamides, polyacrylates,
polymethacrylates, poly vinyl chlorides, polyethylene,
polysiloxane, silicones, cellulose acetates, nitrocellulose,
natural rubber, starch, shellac, and a combination thereof.
[0275] Item 84. The abrasive article of item 74, wherein the
plurality of shaped abrasive particles of the first portion further
comprise a first grinding efficiency characteristic selected from
the group consisting of: a major surface grinding efficiency upper
quartile value (MSUQ) not greater than about 8.3 kN/mm2; a major
surface grinding efficiency lower quartile value (MSLQ) not greater
than about 8 kN/mm2; a side surface grinding efficiency upper
quartile value (SSUQ) at least about 4.5 kN/mm2; a side surface
grinding efficiency median value (SSM) at least about 3 kN/mm2; a
side surface grinding efficiency lower quartile value (SSLQ) at
least about 2.5 kN/mm2; a maximum quartile difference (MQD) at
least about 6 kN/mm2; a major surface-to-side surface quartile
percent overlap (MSQPO) of not greater than about 11%, a major
surface grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD) of at least about 1.9
kN/mm2; a major surface-to-side surface upper quartile percent
difference (MSUQPD) of at least about 54%; a major surface-to-side
surface lower quartile percent difference (MSLQPD) of at least
about 28%; a major surface grinding efficiency time variance (MSTV)
is not greater than about 2 kN/mm2; and a combination thereof.
[0276] Item 85. The abrasive article of item 84, wherein the batch
further comprises a second portion of shaped abrasive particles,
wherein the second portion of shaped abrasive particles have a
second grinding efficiency characteristic different than a first
grinding efficiency characteristic of the first portion, wherein
the second grinding efficiency characteristic is selected from the
group consisting of: a major surface grinding efficiency upper
quartile value (MSUQ); a major surface grinding efficiency median
value (MSM); a major surface grinding efficiency lower quartile
value (MSLQ); a side surface grinding efficiency upper quartile
value (SSUQ); a side surface grinding efficiency median value
(SSM); a side surface grinding efficiency lower quartile value
(SSLQ); a major surface-to-side surface grinding orientation
percent difference (MSGPD); a maximum quartile-to-median percent
difference (MQMPD); a maximum quartile difference (MQD); a major
surface-to-side surface quartile percent overlap (MSQPO); a major
surface grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD); a major surface-to-side
surface upper quartile percent difference (MSUQPD); a major
surface-to-side surface lower quartile percent difference (MSLQPD);
wherein the major surface grinding efficiency time variance (MSTV);
and a combination thereof.
[0277] Item 86. The abrasive article of item 85, wherein at least
one of the first grinding efficiency characteristics of the first
portion is different as compared to a corresponding second grinding
efficiency characteristic of the second portion by at least about
2%, at least about 5%, at least about 8%, at least about 10%, at
least about 12%, at least about 25%, at least about 18%, at least
about 20%, at least about 22%, at least about 25%.
[0278] Item 87. The abrasive article of item 85, wherein at least
one of the first grinding efficiency characteristics of the first
portion is greater than a corresponding second grinding efficiency
characteristic of the second portion by at least about 2%, at least
about 5%, at least about 8%, at least about 10%, at least about
12%, at least about 25%, at least about 18%, at least about 20%, at
least about 22%, at least about 25%.
[0279] Item 88. The abrasive article of item 85, wherein at least
one of the first grinding efficiency characteristics of the first
portion is less than a corresponding second grinding efficiency
characteristic of the second portion by at least about 2%, at least
about 5%, at least about 8%, at least about 10%, at least about
12%, at least about 25%, at least about 18%, at least about 20%, at
least about 22%, at least about 25%.
[0280] Item 89. The abrasive article of item 74, wherein the first
portion comprises a majority of a total number of shaped abrasive
particles of the batch.
[0281] Item 90. The abrasive article of item 74, wherein the first
portion comprises a minority of a total number of shaped abrasive
particles of the batch.
[0282] Item 91. The abrasive article of item 74, wherein the first
portion defines at least 1% of a total number of shaped abrasive
particles of the batch.
[0283] Item 92. The abrasive article of item 74, wherein the first
portion defines not greater than about 99% of a total number of
shaped abrasive particles of the batch.
[0284] Item 93. The abrasive article of item 74, wherein the batch
further comprises a second portion of abrasive particles, the
second portion including crushed abrasive particles having random
shapes.
[0285] Item 94. The abrasive article of item 74, wherein the batch
further comprises a second portion of abrasive particles, the
second portion including diluent abrasive particles.
[0286] Item 95. A method comprising: removing material from a
workpiece by moving an abrasive article relative to a surface of
the workpiece, the abrasive article comprising: a backing; and a
batch of abrasive particles comprising a first portion including a
plurality of shaped abrasive particles overlying the backing,
wherein the plurality of shaped abrasive particles of the first
portion comprise at least one first grinding efficiency
characteristic of: a major surface-to-side surface grinding
orientation percent difference (MSGPD) of at least about 40%; a
maximum quartile-to-median percent difference (MQMPD) of at least
about 48% a major surface grinding efficiency median value (MSM) of
not greater than about 4 kN/mm2; and a combination thereof.
[0287] Item 96. The method of item 95, wherein the fixed abrasive
article comprises a coated abrasive article including a single
layer of the batch overlying the backing.
[0288] Item 97. The method of item 95, wherein a majority of the
plurality of shaped abrasive particles of the first portion of the
batch are arranged in a side orientation relative to the
backing.
[0289] Item 98. The method of item 95, wherein a majority of the
plurality of shaped abrasive particles of the first portion of the
batch comprise a substantially random rotational orientation
relative to the backing.
[0290] Item 99. The method of item 95, wherein a majority of the
plurality of shaped abrasive particles of the first portion of the
batch comprise a substantially random rotational orientation
relative to a predetermined grinding direction.
[0291] Item 100. The method of item 95, wherein at least about 55%
of the plurality of shaped abrasive particles of the first portion
are oriented in a side orientation, at least about 60%, at least
about 65%, at least about 70%, at least about 75%, at least about
77%, at least about 80%, at least about 82%, and not greater than
about 99%.
[0292] Item 101. The method of item 95, wherein the plurality of
shaped abrasive particles of the first portion define an open coat,
wherein the open coat comprises a coating density of not greater
than about 70 particles/cm2, not greater than about 65
particles/cm2, not greater than about 60 particles/cm2, not greater
than about 55 particles/cm2, not greater than about 50
particles/cm2, at least about 5 particles/cm2, at least about 10
particles/cm2.
[0293] Item 102. The method of item 95, wherein the plurality of
shaped abrasive particles of the first portion define a closed
coat, wherein the closed coat comprises a coating density of at
least about 75 particles/cm2, at least about 80 particles/cm2, at
least about 85 particles/cm2, at least about 90 particles/cm2, at
least about 100 particles/cm2.
[0294] Item 103. The method of item 95, wherein the backing
comprises a woven material, wherein the backing comprises a
non-woven material, wherein the backing comprises an organic
material, wherein the backing comprises a polymer, wherein the
backing comprises a material selected from the group consisting of
cloth, paper, film, fabric, fleeced fabric, vulcanized fiber, woven
material, non-woven material, webbing, polymer, resin, phenolic
resin, phenolic-latex resin, epoxy resin, polyester resin, urea
formaldehyde resin, polyester, polyurethane, polypropylene,
polyimides, and a combination thereof.
[0295] Item 104. The method of item 95, wherein the backing
comprises an additive chosen from the group consisting of
catalysts, coupling agents, curants, anti-static agents, suspending
agents, anti-loading agents, lubricants, wetting agents, dyes,
fillers, viscosity modifiers, dispersants, defoamers, and grinding
agents.
[0296] Item 105. The method of item 95, further comprising an
adhesive layer overlying the backing, wherein the adhesive layer
comprises a make coat, wherein the make coat overlies the backing,
wherein the make coat is bonded directly to a portion of the
backing, wherein the make coat comprises an organic material,
wherein the make coat comprises a polymeric material, wherein the
make coat comprises a material selected from the group consisting
of polyesters, epoxy resins, polyurethanes, polyamides,
polyacrylates, polymethacrylates, poly vinyl chlorides,
polyethylene, polysiloxane, silicones, cellulose acetates,
nitrocellulose, natural rubber, starch, shellac, and a combination
thereof.
[0297] Item 106. The method of item 95, wherein the adhesive layer
comprises a size coat, wherein the size coat overlies a portion of
the plurality of shaped abrasive particles, wherein the size coat
overlies a make coat, wherein the size coat is bonded directly to a
portion of the first abrasive particle, wherein the size coat
comprises an organic material, wherein the size coat comprises a
polymeric material, wherein the size coat comprises a material
selected from the group consisting of polyesters, epoxy resins,
polyurethanes, polyamides, polyacrylates, polymethacrylates, poly
vinyl chlorides, polyethylene, polysiloxane, silicones, cellulose
acetates, nitrocellulose, natural rubber, starch, shellac, and a
combination thereof.
[0298] Item 107. The method of item 95, wherein the plurality of
shaped abrasive particles of the first portion further comprise a
first grinding efficiency characteristic selected from the group
consisting of: a major surface grinding efficiency upper quartile
value (MSUQ) not greater than about 8.3 kN/mm2; a major surface
grinding efficiency lower quartile value (MSLQ) not greater than
about 8 kN/mm2; a side surface grinding efficiency upper quartile
value (SSUQ) at least about 4.5 kN/mm2; a side surface grinding
efficiency median value (SSM) at least about 3 kN/mm2; a side
surface grinding efficiency lower quartile value (SSLQ) at least
about 2.5 kN/mm2; a maximum quartile difference (MQD) at least
about 6 kN/mm2; a major surface-to-side surface quartile percent
overlap (MSQPO) of not greater than about 11%, a major surface
grinding efficiency median value and side surface grinding
efficiency median value difference (MSMD) of at least about 1.9
kN/mm2; a major surface-to-side surface upper quartile percent
difference (MSUQPD) of at least about 54%; a major surface-to-side
surface lower quartile percent difference (MSLQPD) of at least
about 28%; a major surface grinding efficiency time variance (MSTV)
is not greater than about 2 kN/mm2; and a combination thereof.
[0299] Item 108. The method of item 95, wherein the first portion
comprises a majority of a total number of shaped abrasive particles
of the batch.
[0300] Item 109. The method of item 95, wherein the first portion
comprises a minority of a total number of shaped abrasive particles
of the batch.
[0301] Item 110. The method of item 95, wherein the first portion
defines at least 1% of a total number of shaped abrasive particles
of the batch.
[0302] Item 111. The method of item 95, wherein the first portion
defines not greater than about 99% of a total number of shaped
abrasive particles of the batch.
[0303] Item 112. The method of item 95, wherein the batch further
comprises a second portion of abrasive particles, the second
portion including crushed abrasive particles having random
shapes.
[0304] Item 113. The method of item 95, wherein the batch further
comprises a second portion of abrasive particles, the second
portion including diluent abrasive particles.
* * * * *